can someone help me with this please and explain because i’m confused :)) thanks!

Can Someone Help Me With This Please And Explain Because Im Confused :)) Thanks!

Answers

Answer 1

Answer: 0.2121...=7/33     ≈943 hits

Step-by-step explanation:

a.

[tex]99n=100n-n\\[/tex]

Divide both parts of the equation by 99:

[tex]\displaystyle\\n=\frac{100n-n}{99} \\\\n=\frac{100*0.2121...-0.2121...}{99} \\\\n=\frac{21.2121...-0.2121...}{99}\\\\n=\frac{21}{99} \\\\n=\frac{7*3}{33*3}\\\\n=\frac{7}{33}[/tex]

b.

[tex]\displaystyle\\200:\frac{7}{33}=\\\\200*\frac{33}{7} =\\\\\frac{200*33}{7}=\\\\\frac{6600}{7}=\\\\ \approx943[/tex]


Related Questions

The mode is the value of the observation that appears most frequently. true or false

Answers

The statement 'The mode is the value of the observation that appears most frequently.' is True.

We know that, the mode is the most frequent number.

It is the number that occurs the highest number of times.

The observation occurring the most number of times or which has highest frequency is known as the mode.

For example,  in {6, 3, 9, 6, 6, 5, 9, 3} the Mode is 6 as it occurs most often.

There is no mode when all observed values appear the same number of times in a data set.

Therefore, the statement 'The mode is the value of the observation that appears most frequently.' is True.

Learn more about the mode here:

https://brainly.com/question/6813742

#SPJ4

2-2 logic geometry need the answers by today if available

Answers

Answer:

can you put a better pic

Step-by-step explanation:

Find the percent of decrease from 136 days to 85 days. round the percent to the nearest tenth if necessary.

Answers

The percent of decrease from 136 days to 85 days to the nearest tenth is 37.5%

Percentage decrease

Original days = 136 daysNew days = 85 days

Change in number of days = Original days - New days

= 136 days - 85 days

= 51 days

Percentage decease = Change in number of days / Original days × 100

= 51 / 136 × 100

= 0.375 × 100

= 37.5%

Therefore, the percent of decrease from 136 days to 85 days to the nearest tenth is 37.5%

Learn more about percentage decrease:

https://brainly.com/question/11360390

#SPJ4

Swati played eight basketball games this season. her point totals for each game were 8, 14, 4, 7, 6, 14, 4, and 7. what was the mean number of points she scored per game? 7 8 9 10

Answers

The Mean number of points she scored per game is 8.

Mean is defined as the average value of the given set of data .

mean is calculated by dividing the (sum of all observations) with (total number of observations).

For Example , Smith scored 8,6,10 out of 10 in his three tests.

so the mean score of smith will be [tex]\frac{8+6+10}{3} =\frac{24}{3} =8[/tex].

In the given question

Points for each game = 8, 14, 4, 7, 6, 14, 4, and 7.

Sum of all the points = 64.

Total number of basketball games =8

[tex]Mean= \frac{Sum of all the points }{total number of games} \\ \\ Mean=\frac{64}{8} =8.[/tex]

Therefore , the mean number of points Swati scored per game is 8.

Learn more about Mean here https://brainly.com/question/25822958

#SPJ4

Answer:

it is 8 the mean is 8

Step-by-step explanation:

Eric had 2 picnic baskets. He put 7 apples in each one. How many apples did he put into the picnic baskets.

Answers

Answer:

14

Step-by-step explanation:

Answer:

14

Step-by-step explanation:

2 x 7 = 14 apples

Plsss helppppp meeee

Answers

Answer: C

Step-by-step explanation:

g(7) = 7/8 (7)  - 1/2

g(7) = 6.125  - 1/2

g(7) = 5.625   OR in fraction form, 45/8

The answer is C

solve 9x + 7 = 12x - 3
and 4 1/2x = 3x - 1
find x please show your work!!

Answers

9x+7 = 12x-3
9x-12x=-3-7
-3x=-10
Answer: 10/3 = 3 1/3

4 1/2x =3x-1
9/2x = 3x-1
9x=6x-2
9x-6x=-2
3x=-2
Answer: -2/3

Last week a painter painted 4 houses in 6 days. what is the productivity of the painter? calculate your answer to 2 decimal places.

Answers

The productivity of the painter is 0.66 up to two decimal places. It is attained by applying the knowledge of the division of two numbers and decimals to the provided problem.

What is decimal?

A decimal is a quantity that is distributed into two components, namely a whole and a fraction. A decimal number represents the numerical value lying in between the two integers. A decimal point (.) is used to segregate the fractional part from the whole part of a number.

E.g. 1.5, 0.06, 7.05, etc.

Calculation of the productivity of the painter

Productivity of the painter is obtained by dividing the number of houses painted by the number of days taken to paint them

The number of houses painted is 4

The number of days taken to paint 4 houses is 6 days

Productivity = 4 ÷ 6

                  = 0.666

Thus, the productivity of the painter is 0.66 up to two decimal places.

To learn more about the decimal of a given number, visit the link below:

https://brainly.com/question/20720302

#SPJ4

A fruit stand is swlling mandarin oranges for $6 for 4 pounds. a mandarin orange weighs about 2 ounces. there are 16 oumces in a pound. at this rate, how many mandarin oranges can you buy for $

Answers

The number of mandarin oranges one can buy for $9 is 48 oranges. It is calculated using basic arithmetic operations.

What are arithmetic operations?

Arithmetic operations are the basic mathematical operations which deal with simple calculations. It involves addition (+), subtraction (-), multiplication (×), and division (÷). Arithmetic operations can be used to combine two or more expressions in some or the other way.

Calculation of the number of mandarin oranges one can buy for $9

We are given that,

$6 = 4 pounds

Using arithematic operation division,

Dividing by 6 into both sides, we have,

$1 = 4 / 6 pounds

$1 = 2 / 3 pounds

Using arithematic operation multiplication,

Multiplying the above equation with 9 on both sides,

$9 = (2 / 3) * 9 pounds

$9 = 6 pounds              - - - - - (1)

According to the given question,

1 orange  weighs 2 ounces         - - - - -(2)

1 pound = 16 ounces                  

1 pound = 8 × (2 ounces)

Using equation 2,

1 pound = 8 oranges

Using equation 1,

$9 = 6 (8 oranges)

$9 = 48 oranges

Hence, one can buy 48 oranges for 9 dollars i.e. $9.

To learn more about arithmetic operations, visit here:

https://brainly.com/question/13181427

#SPJ4

Alvin decided to buy Samantha some candy. He bought her 6 lollipops and 5 petits 4 for $1.40 and then he decides to buy Megan 5 lollipops and 6 petits 4 for $1.35. How much did each cost

Answers

Lollipops costs $0.15

Petits costs $0.1

How to calculate the cost of lollipops and petits ?

let x represent the cost of lollipops

let y represent the cost of petits

6x + 5y = 1.40.........equation 1

5x + 6x= 1.35.........equation 2

From equation 1

6x + 5y= 1.40

6x= 1.40 -5y

x= 1.40-5y/6

Substitute 1.40-5y/6 for x in equation 2

5(1.40-5y/6) + 6y = 1.35

7-25y/6 + 6y= 1.35

7-25y+36y/6= 1.35

cross multiply

7 +11y= 8.1

11y= 8.1-7

11y= 1.1

y= 1.1/11

y= 0.1

Substitute 0.1 for y in equation 1

6x +5y= 1.40

6x + 5(0.1)= 1.40

6x + 0.5= 1.40

6x= 0.9

x= 0.9/6

x= 0.15

Hence the cost of lollipops is $0.15 and cost of petits is $0.1

Read more on cost here

https://brainly.com/question/13683679?referrer=searchResults

#SPJ1

A mobile phone company reported a 170% increase in sales in one year.
At the start of the year sales were 3 million.
What was the sales increase over the year?
million

Answers

The increase in sales after 170% increase with the initial sales 3 million is

5,100,000 (5 million and 1 lakh or 51 lakh).

Percentage means a number or a ratio represented in the form of fractions of 100. It is represented using the percentage sign ‘%’. The abbreviations used to represent the percentage are ‘pct’ or ‘pc’. In other words, the percentage is defined as how much of one quantity is made by another quantity and it is evaluated in terms of 100.

We have to increase the value by 170%.

The value of the percentage increase = 170% × 3,000,000

The new value = 3,000,000 + The value of the percentage increase

The new value = 3,000,000 + The value of the percentage increase

=3,000,000 + (170% × 3,000,000) = 3,000,000 + 170% × 3,000,000

=(1 + 170%) × 3,000,000 = (100% + 170%) × 3,000,000

=270% × 3,000,000 = 270 ÷ 100 × 3,000,000

=270 × 3,000,000 ÷ 100 = 810,000,000 ÷ 100

=8,100,000 million.

The actual change = The new value - 3,000,000

=8,100,000 - 3,000,000

=5,100,000 million or 5.1 million.

To learn more about percentage visit:

brainly.com/question/16797504

#SPJ1


Parker says that any two congruent acute triangles can be arranged to make a rectangle. Tamika says that only two congruent right triangles can be arranged to make a rectangle. Is either of them correct? Explain your reasoning.

Answers

The statement of Tamika  is correct.

How many congruent triangles do you need?

Recall that we designate an angle as a place where two line meet. The magnitude of the angle could be measured by the use of a compass. A right angle triangle is a triangle that has an angle of ninety degrees as one of the angles.

Let us keep in mind that all the sides of a rectangle must have an angle of ninety degrees. This is because the sum of the angles in a rectangle must sum up to a total of three hundred and sixty degrees.

Having said that; when we consider the statements of the two persons and reason that if we have two right angled triangles, we could be able to make a rectangle because the four right angles that are required could be cut out of the two congruent right angled triangles. This implies that the statement of Tamika  is correct.

Learn more about congruent triangles:https://brainly.com/question/22062407

#SPJ1

Evaluate this function please:
f(g(2))

Answers

Answer: 2fg

Step-by-step explanation:

Rewrite using the commutative property of multiplication = 2fg

research looks at how variables vary with each other, while research looks at how one variable causes a change in another variable. descriptive; correlational correlational; experimental experimental; descriptive experimental; correlational

Answers

"Correlational" research looks at how variables vary with each other, while "experimental" research looks at how one variable causes a change in another variable.

What is correlational research?

Research is a form of non-experimental methodology in which a researcher measures 2 factors and analyzes and evaluates the statistical relationship among them without the influence of any other variable.

Some key features regarding the correlational research are-

The correlation coefficient (a statistical technique that determines the strength of the connection between two variables) shows this same correlation between two variables, with a value ranging from -1 to +1. A positive correlation exists between the two variables so when correlation coefficient is close to +1. If the value is close to -1, the two variables have a negative correlation. Whenever the value is close to zero, the two variables have no relationship.

To know more about the correlational research, here

https://brainly.com/question/4272060

#SPJ4

suppose a jar contains 9 red marbles and 14 blue marbles. if you reach in the jar and pull out 2 marbles at random at the same time, find the probability that both are red. answer should be in fractional form.

Answers

Answer: 2/23

Step-by-step explanation:

9+14=23

Janine is packing carrots. each large box holds 20 2-pound bags of carrots. if janine has 800 bags of carrots, how many boxes can she fill? a. 20 boxes b. 40 boxes c. 80 boxes d. 200 boxes

Answers

The total number of boxes required for packing the carrots is 40 boxes.

What do you mean by the unitary method?

The unitary approach is a strategy for problem-solving that involves first determining the value of a single unit, then multiplying that value to determine the required value. The unitary technique, in essence, determines the value of a unit from the value of a multiple. To put it simply, it determines the value of a single unit from a given multiple. How can you figure out the price of one pen if 100 cost Rs. 400? You can reach the solution using the unitary technique. Additionally, after a single unit's value has been established, the values of the other units can be derived by multiplying the original unit's value.

Janine is carrying carrots because of this. There are 20 2-pound bags of carrots in each huge box.

We must determine how many boxes Janine can fill.

Now, 800/20=40 boxes are equal to the total number of bags/bags each box can contain.

This means that a total of 40 boxes are needed to load the carrots.

To learn more about the unitary method, Visit:

https://brainly.com/question/930571

#SPJ4

A description of the distribution of the values of a random variable and their associated probabilities is called a.

Answers

A description of the distribution of the values of a random variable and their associated probabilities is called a Probability Distribution.

What is a random variable?

Understanding the random variable and its probability is necessary for the analysis of complex random occurrences. The numerical result of a random process, which might be discrete or continuous in nature, is known as a random variable.

Now,

If the result of the random variable is tabulated along with the probabilities, it makes it easier to analyze random events. A probability distribution table is a description of the distribution of the values of a random variable along with their probabilities. Graphs and mathematical formulas can both be used to represent the probability distribution.

Hence, A description of the distribution of the values of a random variable and their associated probabilities is called a Probability Distribution.

To learn more about random variables, refer to the link: https://brainly.com/question/17217746

#SPJ4


The area of a triangle is 16 square units. The base of the triangle is x+4 and the height is x . Find x

Answers

Answer:

4

Step-by-step explanation:

There are 60 people in a choir.
Half of the people in the choir are women.

The number of women in the choir is 3 times the number of men in the choir.
The rest of the people in the choir are children.

the number of children in the choir : the number of men in the choir
= n : 1
Work out the value of n.

Answers

Answer:

There are 60 people in the chior so we will be dividing that number up to see how many women men and children there are. Half of them are women, which mean divide 60 by 2 which equals 30. There are 30 women in the choir. The number of women is 3 times compared to men. Since its 3 times we use the commutative property of division. 30 divided by 3 is 10. There are 10 men in the choir. The rest are children. To find the rest of them we will take how many people in the choir we know so far and then subtract from the total: 60. there are 30 women and 10 men which adds up to 40. 60 minus 40 equals 20. There are 20 children in the choir.

Since n = number of men and children:

n = 30

30 : 1

Step-by-step explanation:

Hope it helps! =D

how would ninteen billion,eighty-seven thousand,three hundred fourteen be written in standard form

Answers

Answer: 190,870,314

Step-by-step explanation:

It would be 190,870,314

The pie chart below shows information about
the electronic devices that a shop sold in
January.
The shop sold 900 electronic devices in total in
January.
In February, the shop sold the same numbers of
tablets, desktop computers and laptops as in
January, but sold 40% more mobile phones.
If a second pie chart was drawn showing the
shop's sales in February, what would the central
angle of the mobile phones section be?
Give your answer in degrees (°) to 1 d.p.
Electronic devices sold in January
70°
84
60
146°
Key
Desktop computer
Laptop
Tablet
Mobile phone
Not drawn accurately

Answers

The central angle of mobile phones section in February be 91°

Given,

The total number of electronic devices sold by a shop in January = 900

According to pie chart

900 implies 360°. Therefore, 900/360 = 2.5

Now lets check the number of devices sold in January:

Desktop = 60° ⇒ 60 × 2.5 = 150

Laptop = 146° ⇒ 146 × 2.5 = 365

Tablet = 84° ⇒ 84 × 2.5 = 210

Mobile = 70° ⇒ 70 × 2.5 = 175

Its given that in February, all other numbers are same except Mobile phones.

40% more mobile phones are sold in February than in January.

So, number of mobile phones sold in February = 175 × (140/100) = 245

Now lets calculate the total number of devices sold in February:

900 - 175 = 725

725 + 245 = 970

970 devices sold in February.

According to pie chart:

970 implies 360 = 970/360 = 2.69

Now lets check the degree in pie chart for each devices,

Desktop = 150 ⇒ 150/2.69 = 55.7°

Laptop = 365 ⇒ 365/2.69 = 135.5°

Tablet = 210 ⇒ 210/2.69 = 78°

Mobile = 245 ⇒ 245/2.69 = 91°

That is, the central angle of mobile phones section in February be 91°

Learn more about pie chart here:

https://brainly.com/question/9979761

#SPJ1

Does anybody dirt bike??

Answers

Answer:

Yes, some

Step-by-step explanation:

The probability of the states of nature, after use of bayes' theorem to adjust the prior probabilities based on given indicator information, is called _____.

Answers

The probability of natural states after applying the Bayes theorem to modify the prior probabilities in light of available indicator data is known as the posterior probability.

What is posterior probability?

The posterior probability is a type of conditional probability that is created by applying the Bayes theorem to update the prior probability with information that is summarized by the likelihood. From an epistemological standpoint, the posterior probability, given prior knowledge and a mathematical model describing the observations available at a specific time, contains all that is known about an uncertain proposition (such as a scientific hypothesis, or parameter values).  The present posterior probability may act as the prior in a subsequent round of Bayesian updating following the arrival of new data. The posterior probability distribution often expresses the epistemic uncertainty regarding statistical parameters conditional on a set of observed data in the context of Bayesian statistics.

To know more about  posterior probability, visit:

https://brainly.com/question/17010130

#SPJ4

how many significant figures are in the measurement 0.00001 meters?

Answers

Answer:

1 significant figure

Step-by-step explanation:

Zero is significant when:

It occurs between two non-zero integers, such as 408; it occurs at the end of a number that contains a decimal point, such as 570. or 1.300

Zero is not significant when:

It is before the first non-zero integer, such as 0.0057 (two significant figures); it is at the end of a number that does not contains a decimal point, such as 253,000 (three significant figures)

(trust me I'm taking chemistry this year and literally that is the 'rule' that is written down in my notebook)

Como se lee 78,004,000

Answers

Answer: seventy-eight million

Step-by-step explanation:

seventy eight million four thousand / setenta y ocho million cuatro mil

5. A state began an effort to increase the
deer population. In year 2 of the ef-
fort, the deer population in a state
forest was 2,400. In year 4, the pop-
ulation was 3,456. Write an explicit
rule for the sequence using subscript
notation.

Answers

The explicit rule for the sequence using subscript notation is [tex]a_n=2000\times1.2^{n-1}[/tex] .

Explicit expressions are always used to represent any term in a sequence without describing any other term in the sequence. The meaning of "explicit" is direct, something that can be found directly  without knowing the other terms in the sequence.A term in a sequence can be uniquely represented by a single expression, an explicit expression. Geometric Sequence: [tex]a_n=ar^{n-1}[/tex], where 'a' is the first term and 'r' is the common ratio.

It is given that sequence is G.P

In G.P 2nd and 4th is given by

 [tex]a_2=ar[/tex]      ...(1)      and              [tex]a_4=ar^3[/tex]  ...(2)

We have given [tex]a_2=2400 , a_4=3456[/tex]

Putting in equation (1) and (2) , we get

       [tex]2400=ar[/tex]    ...(3)          and           [tex]3456=ar^3[/tex]      ...(4)

On dividing equation (3) by equation (4) , we get

        [tex]\frac{2400}{3456} =\frac{ar}{ar^3} \\\\\\ 0.6944=\frac{1}{r^2}\\\\r^2=1.44 \\r=1.2[/tex]

First term will be given by

       [tex]a_1=a_2 r^{1-2}\\\\a_1=2400r^{-1}\\\\a_1=\frac{2400}{1.2} \\\\a_1=2000[/tex]

Nth term is given by

[tex]a_n=a_1r^{n-1}\\a_n=2000\times1.2^{n-1}[/tex]

Learn more about sequence here :

https://brainly.com/question/17615101

#SPJ9

suppose that 26% of people own dogs. if you pick two people at random, what is the probability that they both own a dog?

Answers

The probability of both owning a dog is 0. 52

What is probability?

Probability can be defined as the chance that a given event occurs.

From the information given, we have that;

The probability of owning a dog is 26%

Let's convert to decimal

Probability of owning a dog = 26 / 100 = 0.26

P(2 people) = 2 × P(owning a dog)

P(2 people) = 2 × 0. 26

Multiply through

P(2 people) = 0. 52

The probability of both owing a dog is 0.52

Thus, the probability of both owning a dog is 0. 52

Learn more about probability here:

https://brainly.com/question/25870256

#SPJ4

which is greater height or radius of cone?
full explanation down below

Answers

The 150 m³ cone that has a base radius of 5 meters indicates that the height of approximate length 5.73 meters is greater than the radius (length 5 meters)

How can the height of the cone be found?

The given parameters are;

Volume of the cone is V = 150 m³

Base radius of the cone, r = 5 m

The formula for finding the volume of a cone is; [tex]V = \mathbf{\frac{1}{ 3} \cdot \pi \cdot {r}^{2} \cdot h} [/tex]

By plugging in the values for the volume, V and radius, r, of the cone, we have;

[tex]150 = \frac{1}{ 3} \times \: \pi \times {5}^{2} \times h[/tex]

Which gives;

[tex] h = \mathbf{ \frac{150}{ \frac{1}{ 3} \times \: \pi \times {5}^{2} } \approx 5.73} [/tex]

Therefore;

The height, (h ≈ 5.73 meters) is greater than the radius, r = 5 meters

Learn more about finding the volume of regular solids here:

https://brainly.com/question/17244531

#SPJ1

answer with show work!

continuing question.

What pattern would have 64 squares?
Write down an expression, in terms of n, for the number of squares in Pattern n.

Answers

Answer:

Pattern 8 would have 64 squares.

Step-by-step explanation:

Ok, I understand, Pattern 4 would have 16 squares, so we have to continue adding the pattern.

5 = 25, 6 = 36, 7 = 49, and 8 = 64. The key to this is each pattern number is multiplied BY ITSELF.

Hope this helps!

Sorry for being a little rude previous question, I didn't have a reference.

find the prime factorization of 85

Answers

The prime factors of 85 is 5 and 17

Prime factorisation:

Finding the prime factors of a given number, such as a composite number, is done through the process of prime factorization. The prime numbers are the only components in these factors. A number with just the number itself and factor 1 is said to be a prime number.

Factor:

the quantities that are multiplied to produce new quantities are called Factor.

Prime factors:

A prime factor is a factor that is a prime number and not a composite number.

85=5×17

Therefore,The prime factors of 85 is 5 and 17

     

Learn more about prime factors here:

https://brainly.com/question/10454590

#SPJ4

Other Questions
Ahmad is loading a pallet with boxes that eachweighs 45 pounds. The pallet can safelysupport no more than 900 pounds. How manyboxes can Ahmad safely load onto the pallet? phospholipids tend to group together so that their polar parts face the surrounding aqueous environment, while their hydrophobic tails face each other. the resulting structures are called . Question 15 of 36A scientist who examines fossilized bones in order to determine the genus ofan animal is most likely a:OA. paleontologist.OB. meteorologist.C. geologist.OD. climatologist.SUBMIT Xplain the difference between adverse selection and moral hazard in insurance markets. can one exist without the other? How does the working distance of a microscope chnage when you increase the magnification? What kind of proteins are lacking or low in one area, like beans, grains, nuts, and vegetables?complete proteinscomprehensive proteinsincomplete proteinswhole proteins 3. If there were less seafloor spreading occurring at mid-ocean ridges than subduction at ocean trenches, what would happen to the seafloor in the ocean? a. Nothing would happen. The ocean's seafloor would stay the same. b. The ocean's seafloor would sink into the mantle below. c. The ocean's seafloor would get smaller, losing more crust than is created. d. The ocean's seafloor would grow, creating more crust than is destroyed. 55. There are about 0.62 miles in one kilometer. If Darnell is runninga race that is 5.5 kilometers long, about how many miles is the race?Did you multiply or divide to find your answer? which neurotransmitter is associated with processing of information, regulation of mood, behavior, and thought processes? Which attack method involves encoding portions of the attack with unicode, utf-8, or url encoding? two f1 plants were crossed with each other and the f2 generation consisted of 860 tall plants with purple flowers; 285 dwarf, purple plants; 340 tall, pink plants; and 115 dwarf, pink plants (1600 total). a chi-square goodness-of-fit test is used to see if these data represent chance deviations from a 9:3:3:1 ratio. what will be the calculated chi-square value and what will be the degrees of freedom used to interpret the chi-square? How do details support a central idea in an informational text which is the appropriate action to take when a patient arrives with an appointment card that states she has a dental appointment that day but the schedule does not indicate an appointment for the patient? What is the equation solve it Match the polynomial expression on the left with the simplified version on the right.(y + 5)(y - 5)(y + 5)A2-10-25+25-10y-25+10y + 25 Pls answer quick donna quit her job at portland, inc. and joined a rival company. portland, inc. accused her of breaking her contractual obligations and decided to take her to court. in this scenario, which component of social justice is involved? When a firm puts up collateral assets to back up a loan, the debt is said to be? 4 cards are drawn at random from a standard deck. find the probability that all the cards are hearts. find the probability that all the cards are face cards. note: face cards are kings, queens, and jacks. find the probability that all the cards are even. (consider aces to be 1, jacks to be 11, queens to be 12, and kings to be 13) no modifications or additions that affect the capacity or safe operation of a crane or derrick should ever be made without: An element has two stable isotopes. One has a mass of 6.015 amu and is 7.59 abundant. The second has a mass of 7.016 amu and is 92.41 abundant what is the average mass of the element. What is the average atomic mass of the element