Evaluate 4(3.1+2) 20 20.8 24

Paul bought 2.25 meters of wood to make 5 shelves of equal length . What is the length of each shelf ? show your work on a picec

LiRa [457]

Answer:

Length of each shelf is 0.45 meters

Step-by-step explanation:

Given

$Total\ Length = 2.25\ meters$

$Shelves = 5$

Required

Determine the length of each shelf

This is calculated by dividing the total length by number of shelves as thus:

$Length = Total\ Length/Number\ of\ Shelf$

$Length = 2.25m /5$

$Length = 0.45m$

Hence;

<em>Length of each shelf is 0.45 meters</em>

3 0

3 years ago

Read 2 more answers

A skateboarding ramp is 13 inches high and rises at an angle of 12 degrees. How long is the base of the ramp?

zaharov [31]

144 + 13 !!!!!!!!!!!!!!!

7 0

3 years ago

Read 2 more answers

Which of the following are equations for the line shown below? Check all that

ohaa [14]

Answer:

D. y = -4x - 6

Step-by-step explanation:

→ Work out gradient of line

$\frac{2-6}{-2--3} =\frac{-4}{1} =-4$

→ Write into y = mx + c format

y = -4x + c

→ Substitute ( -2 , 2 ) into the equation to find c

2 = 8 + c

→ Minus 8 from both sides

-6 = c

→ Write full equation y = -4x - 6

7 0

3 years ago

What is the new volume of a rectangular prism that is originally one thousand two hundred fifty cubic meters and is then resized

guajiro [1.7K]

The new volume would be 25

4 0

4 years ago

Given two dependent random samples with the following results: Population 1 71 68 50 84 76 76 80 79 Population 2 76 63 54 80 79

skelet666 [1.2K]

Answer:

$t=\frac{73-73.875}{\sqrt{\frac{(10.570)^2}{8}+\frac{(10.106)^2}{8}}}}=-0.169$

$df=n_{1}+n_{2}-2=8+8-2=14$

Since is a bilateral test the p value would be:

$p_v =2*P(t_{(14)}$

So the p value is a very high value and using any significance level given $\alpha=0.2$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, so we can conclude that the means are similar for both groups

Step-by-step explanation:

Data given and notation

1:[71 68 50 84 76 76 80 79]

2:[76 63 54 80 79 82 75 82]

$\bar X_{1}=73$ represent the mean for the sample 1

$\bar X_{2}=73.875$ represent the mean for the sample 2

$s_{1}=10.570$ represent the sample standard deviation for the sample 1

$s_{2}=10.106$ represent the sample standard deviation for the sample 2

$n_{1}=8$ sample size for the group 1

$n_{2}=8$ sample size for the group 2

t would represent the statistic (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the mean for both groups are equal , the system of hypothesis would be:

Null hypothesis: $\mu_{1} = \mu_{2}$

Alternative hypothesis: $\mu_{1} \neq \mu_{2}$

If we analyze the size for the samples both are less than 30 and the population deviations are not given, so for this case is better apply a t test to compare means, and the statistic is given by:

$t=\frac{\bar X_{1}-\bar X_{2}}{\sqrt{\frac{s^2_{1}}{n_{1}}+\frac{s^2_{2}}{n_{2}}}}$ (1)

t-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

In order to calculate the mean and the sample deviation we can use the following formulas:

$\bar X= \sum_{i=1}^n \frac{x_i}{n}$ (2)

$s=\sqrt{\frac{\sum_{i=1}^n (x_i-\bar X)}{n-1}}$ (3)

Calculate the statistic

We can replace in formula (1) the results obtained like this:

$t=\frac{73-73.875}{\sqrt{\frac{(10.570)^2}{8}+\frac{(10.106)^2}{8}}}}=-0.169$

Statistical decision

For this case we don't have a significance level provided $\alpha$ , but we can calculate the p value for this test. The first step is calculate the degrees of freedom, on this case:

$df=n_{1}+n_{2}-2=8+8-2=14$

Since is a bilateral test the p value would be:

$p_v =2*P(t_{(14)}$

So the p value is a very high value and using any significance level given $\alpha=0.2$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, so we can conclude that the means are similar for both groups

5 0

4 years ago