It is desired to pile some logs in layers so that the top layer contains one log, the next layer contains two logs, the next layer contains three logs, and so on; each layer containing one more log than the layer on top of it. There are 190 logs. Can all the log be used in such a grouping, and if so, how many logs are in the bottom layer?​

Answers

Answer 1

Answer:

Yes all of the logs can be used in such a grouping.

We'll have 19 logs in the bottom row (and have 19 rows)

========================================================

Explanation:

Let n be the number of layers. Let T(n) represent how many logs there are total.

If you have 1 layer, then you have 1 log. So we can say that T(1) = 1.If there are n = 2 layers, then we have 1 log on top of two other logs, which leads to 1+2 = 3 logs total. This shows that T(2) = 3.If there are n = 3 layers, then we have 1 log on top of 2 which are on top of 3 at the very bottom. We have 1+2+3 = 6 logs total. So T(3) = 6.Having n = 4 layers gives 1+2+3+4 = 10 logs. So T(4) = 10Having n = 5 layers gives 1+2+3+4+5 = 15 logs. So T(5) = 15

This process continues for however long you like. The sequence 1,3,6,10,15 is the set of triangular numbers, since the logs form a triangular or pyramid shape when stacked this way. To get the nth value in the triangular number sequence, use this formula

T(n) = 0.5*n*(n+1)

---------------

For example, let's say we wanted to find how many logs there were in the fifth layer

T(n) = 0.5*n*(n+1)

T(5) = 0.5*5*(5+1)

T(5) = 15

This matches from earlier.

The purpose of bringing in a formula is to see if we can get T(n) = 190 for some integer n.

-------------------

T(n) = 0.5*n*(n+1)

190 = 0.5*n*(n+1)

190*2 = n(n+1)

380 = n^2+n

0 = n^2+n-380

n^2+n-180 = 0

Applying the quadratic formula will lead to the two solutions: n = -20 and n = 19. We ignore the negative value of n as we can't have a negative number of rows. Therefore, n = 19 is the only valid solution here.

If we wanted to stack 190 logs in this triangular pyramid fashion, then we'll need to have 19 rows. The bottom row will have 19 logs.

----------

Check:

1+2+3+4+5+6+7+8+9+10 = 55

11+12+13+14+15+16+17+18+19 = 135

55+135 = 190

Or you could say,

T(n) = 0.5*n*(n+1)

T(19) = 0.5*19*(19+1)

T(19) = 190

Either way, the answer is confirmed.


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Pls help I’ll brainlest ASAP

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(-2,1) i think that’s the answer
3/5 is the slop 3 up 5 over

‍plz help‍ I NEED IT RN PLZ

A quadrilateral has (blank) sides and (blank) angles

A pentagon has (blank) sides and (blank) angles

A cube (blank) faces

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Step-by-step explanation:

A quadrilateral has (four) sides and (four) angles

A pentagon has (five) sides and (five) angles

A cube (six) faces

hope this helps you.

identify which of the following in NOT equivalent to
[tex]2 \frac{2}{3} [/tex]

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[tex]~\hspace{7em}\textit{rational exponents} \\\\ a^{\frac{ n}{ m}} \implies \sqrt[ m]{a^ n} ~\hspace{10em} a^{-\frac{ n}{ m}} \implies \cfrac{1}{a^{\frac{ n}{ m}}} \implies \cfrac{1}{\sqrt[ m]{a^ n}} \\\\[-0.35em] \rule{34em}{0.25pt}[/tex]

[tex]\boxed{A}\qquad \sqrt[4]{8}\implies \sqrt[4]{2^3}\implies 2^{\frac{3}{4}} \\\\\\ \boxed{B}\qquad \sqrt[4]{2^3}\implies 2^{\frac{3}{4}} \\\\\\ \boxed{C}\qquad 2^{\frac{1}{4}}\times 2^{\frac{1}{2}}\implies 2^{\frac{1}{4}+\frac{1}{2}}\implies 2^{\frac{1+2}{4}}\implies 2^{\frac{3}{4}} \\\\\\ \boxed{D}\qquad \left( 2^{\frac{1}{4}} \right)^{\frac{1}{2}}\implies 2^{\frac{1}{4}\cdot \frac{1}{2}}\implies 2^{\frac{1}{8}}\qquad \textit{\large \checkmark}[/tex]

.
Simplify.
{[2 + 3(−3 – 4) – 3] – 2} ÷ 23

Answers

Answer:

-0.2

Step-by-step explanation:

pls give me brainliest if possible

Mr. Schnee is refinancing his home. His loan officer has presented him with the following two offers; it is worth noting that Mr. Schnee is expecting to move back home to Michigan in five years. Using a system of linear equations, help Mr. Schnee decide which offer to take in order to maximize his benefit. Mr. Schnee has already determined that he definitely wants to refinance as he is currently paying $1,744.67.

4.5% Interest Rate for 30 years with a monthly payment of $1,266.71 with $256 Closing Costs
4.0% Interest Rate for 30 years with a monthly payment of $1,193.54 with $10,362 in Closing Costs

Answers

The option that best suits him is 4.0% Interest Rate for 30 years with a monthly payment of $ 1,193.54 with $ 10,362 in Closing Costs.

Given that Mr. Schnee is refinancing his home, and his loan officer has presented him with two offers, to determine which offer should he take in order to maximize his benefit, the following calculation must be performed:

A) 4.5% Interest Rate for 30 years with a monthly payment of $ 1,266.71 with $ 256 Closing Costs

1,266.71 x 30 x 12 + 256 = X

1,266.71 x 360 + 256 = X

456,015.60 + 256 = X

456,271.60 = X

B)4.0% Interest Rate for 30 years with a monthly payment of $ 1,193.54 with $ 10,362 in Closing Costs

1,193.54 x 30 x 12 + 10,362 = X

1,193.54 x 360 + 10,362 = X

429,674.40 + 10,362 = X

440,036.40 = X

Therefore, the option that best suits him is 4.0% Interest Rate for 30 years with a monthly payment of $ 1,193.54 with $ 10,362 in Closing Costs.

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please help i only have a few minutes!!

what are the measures of 1 and 2?

Answers

Answer:

3;87

Step-by-step explanation:

Since they are complementary, they add up to 90°. This allows you to write the equation

[tex]x+(16x+39) = 90 \rightarrow 17x=90-39 \rightarrow 17x=51 x=\frac{51}{17}=3[/tex]

The second angle measures then [tex]90-3 = 87[/tex]

Determine the slope of the line that contains the given points. E(-5,6), (4, -3) *
1 point
Your answer

Answers

Answer:

-1

Step-by-step explanation:

Use the slope formula to calculate

-3-6/4-(-5)

= -9/9

= -1 (Slope)

HELPPP FAST LIKE 4 minutes left

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Answer: A. 40

Step-by-step explanation:

rewrite equation in slope - intercept form: (Solve for y)
2x-y=7

Answers

Answer:

y = 2x-7

Step-by-step explanation:

I'm not really sure this is the slope-intercept form, as I've never called it like that before, but if it is, there you go.

Answer:

[tex]\huge\boxed{\sf y = 2x - 7}[/tex]

Step-by-step explanation:

Given equation is:

2x - y = 7

Add y to both sides

2x = 7 + y

Invert the equation

7 + y = 2x

Subtract 7 to both sides

y = 2x - 7

This is the required equation in slope-intercept form y = mx + b where m is slope and b is y-intercept.

[tex]\rule[225]{225}{2}[/tex]

Hope this helped!

~AH1807

Explain how to graph a line when given the standard form Ax + By = C of a linear equation.

PLEASE HELP ME

Answers

Step-by-step explanation:

A= C. - By

x. ×

answer by a

huhuhu

Question is in picture
In parallelogram LMNO what is the measure of angle M?

Answers

Answer:

Step-by-step explanation:

∠L and ∠N are identical

3x + 40 = 5x

       40 = 2x

        20 = x

So ∠L and ∠N are both 100°

Internal angles on a quadrilateral sum to 360° and ∠M and ∠O are identical

∠M = (360 - 2(100))/2 = 80°

find the divergence and curl of the vector
F=(3x²y² +2z)i + (3x² + y +yz )j - (3x²z² +2yx + xyz)k

Answers

Divergence:

div(F) = ∂(3x²y² + 2z)/∂x + ∂(3x² + y + yz)/∂y - ∂(3x²z² + 2yx + xyz)/∂z

div(F) = 6xy² + 1 + z - 6x²z - xy

Curl:

curl(F) = [∂(3x² + y + yz)/∂z + ∂(3x²z² + 2yx + xyz)/∂y] i

… … … … … - [∂(3x²y² + 2z)/∂z + ∂(3x²z² + 2yx + xyz)/∂x] j

… … … … … + [∂(3x²y² + 2z)/∂y - ∂(3x² + y + yz)/∂x] k

curl(F) = (-xz - 2x - y) i + (6xz² + yz + 2y + 2) j + (6x - 6x²y) k

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Answer: The angle is a acute angle not obtuse angle.

Step-by-step explanation:

A 16-ounce bottle of Spring water is $2.08. A 20-ounce bottle of Fresh water is $2.40. Which statement about the unit price is true

Answers

hope this helps,

(Info is in attachment)

i need help i don’t understand this i’m a freshman in highschool doing a mi

Answers

It would be C because if you look at how the data lines up it doesn’t line up in a straight line (like the others) making it most likely to be non-linear
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Question 10 of 10
To model some data, Pat ran an exponential regression and found the
regression equation to be y = 0.496.1.3%,
The scatterplot and residual plot are shown.
Scatterplot
Residual plot
y
4
2
Select the true statements.
O A. The model is a good fit because the patterns in the plots are both
curves.
B. The points in the scatterplot follow a line, so a linear model would
fit the data better.
O C. The residual plot changes direction, so a quadratic model would
fit the data better.
D. The model is not a good fit because there is a pattern in the
residual plot.

Answers

Answer:

B.)The points in the scatterplot follow a line, so a linear model would fit the data better

A.)The model is not a good fit because there is a pattern in the residual plot.

Step-by-step explanation:

The linear model would best fit the scatter plot while the quadratic model would fit the residual plot. The true statements are: B and C.

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A linear model is appropriate for data points that lie along a straight line on graph. If the line is not straight but curved and changes direction, a quadratic model is a better model for such data.

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Answer:

so 6x = -6y + 5

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Step-by-step explanation:

The probability of the test showing negative given the person does not have the disease?

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Answers

Answer:

4.47

Step-by-step explanation:

Hope it helps to you

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Answers

Check the picture below.

If a spherical tank 6 m in diameter can be filled with a liquid for $600, find the cost to fill a tank 12 m in diameter.

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Answers

$1,200
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WILL MARK BRAINLIEST IF ANSWER IS CORRECT

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Answers

Answer: the answer is 8

Step-by-step explanation:

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hi have a nice day

20

4

+(2)(5)

=15

Mrs. Goldstein pours 3 juice boxes into a bowl to make punch each juice box hold 236 ml how much juice it does Mrs.Goldstein pour into the bowl

Answers

708 ml

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Approximately what portion of the box is shaded blue?
A.3/5
B.2/3
C.9/10

Answers

Answer:

I think the answer is C.....

litterally nobody answers my questions
my question is the image

Answers

Here you go hope this helps

Which of the following shows the correct solution steps and solution to 4x + 9 = -23?​

Answers

Exact Form:

x

=

7

2

x

=

7

2

Decimal Form:

x

=

3.5

x

=

3.5

Mixed Number Form:

x

=

3

1

2

Answer:

X=3.5

Step-by-step explanation:

What you do is take -9 to 9 and -23. Next subtract -23 and 9. Then drop 4x and then divided 4x by 14 and you will get 3.5 as your answer.

Hope it helped!


Mark breaks up a 9-hour drive into 3 parts. He drives 2 1/2 hours before stopping for lunch. After driving some more, he stops for gas. If the second part of his drive was 1 2/3 longer than the first part, how long did he drive after stopping for gas?

Answers

Answer:

4 1/6 hours

Step-by-step explanation:

2 1/2 + 1 2/3 = 25/6 = 4 1/6

Evaluate the following expression [(15+1)/2-4]*6

Answers

Answer:

24

Step-by-step explanation:

By BODMAS rule,

[ ( 15 + 1 ) / 2 - 4 ] * 6

= [ 16 / 2 - 4 ] * 6

= [ 8 - 4 ] * 6

= 4 * 6

= 24

Based on the information given, the value of the equation will be -48.

From the information given, the expression is given as:

= (15+1)/2-4]*6

We'll solve the bracket first.

= (15+1)/2-4]*6

= (16 / 2 - 4) × 6

= (16/-2) × 6

= -8 × 6

= -48

In conclusion, the value of the equation will be -48.

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what is the value of y so that the equation is true y^2 = -81

Answers

Step-by-step explanation:

to make the equation true the value of y must be.

-1×9²-1×81-81

hope it helps.

stay safe healthy and happy.

Answer:

y=-/+9

Step-by-step explanation:

y^2=81

find the square root

y=positive/negative 9

Guys please i need help on this, i will give brainliest to the right answers

Answers

Answer:

C) Discrete made up of individual points

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