Find the missing length. Leave your answers as radicals in simplest answer

It is claimed that automobiles are driven on average more than 20,000 kilometers per year. To test this claim, 100 randomly sele

kow [346]

Answer:

$t=\frac{23500-20000}{\frac{3900}{\sqrt{100}}}=8.974$

$p_v =P(t_{99}>8.974)=9.43x10^{-15}$

If we compare the p value and the significance level given for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we to reject the null hypothesis, and the actual mean is significantly higher than 20000.

Step-by-step explanation:

1) Data given and notation

$\bar X=23500$ represent the sample mean

$s=3900$ represent the sample standard deviation

$n=100$ sample size

$\mu_o =2000$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to determine if the true mean is higher than 20000, the system of hypothesis would be:

Null hypothesis: $\mu \leq 2000$

Alternative hypothesis: $\mu > 2000$

We don't know the population deviation, so for this case is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$t=\frac{23500-20000}{\frac{3900}{\sqrt{100}}}=8.974$

Calculate the P-value

First we need to calculate the degrees of freedom given by:

$df=n-1=100-1=99$

Since is a one-side upper test the p value would be:

$p_v =P(t_{99}>8.974)=9.43x10^{-15}$

Conclusion

If we compare the p value and the significance level given for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we to reject the null hypothesis, and the actual mean is significantly higher than 20000.

8 0

3 years ago

uring a period of extreme cold, the average daily temperature dropped decreased by 112°Feach day. How many days did it take for

marissa [1.9K]

Answer:

lol

Step-by-step explanation:

7 0

3 years ago

find the length of the long diagonal of a rhombus when it's area of 24 square centimeters and it's short diagonal is 4 centimete

Ivahew [28]

Answer:

12

Step-by-step explanation:

A rhombus is a parallelogram with all four sides equal.

Its diagonals are perpendicular.

Each of the triangles formed by the diagonals and the sides are congruent, so the area of the rhombus is 4 times the area of one of the triangles.

Since the short diagonal is given as 4, each of the triangles can be viewed as having a base of 2. Each triangle's height, h, then is one half the length of the long diagonal.

The are of one of the triangles is 1/2 (base)(height)=(1/2)(2)h

The area of the rhombus is then

4(1/2)(2)h=24

Solving for h gives

h=6

This makes the length of the long diagonal 2h=12

6 0

3 years ago

100 yards on 20 carries

Svetlanka [38]

Answer:

if u multiply 20 times 5 u would get 100 and and if u add 20+20+20+20+20 u would get 100 so either way ur answer may be 5

4 0

3 years ago

Mii need halp<br> im givin brainliest dis time

Irina18 [472]

Answer:

x = 35 , y = 72.5

Step-by-step explanation:

(a)

x and 35° are vertical angles and are congruent, then

x = 35

(b)

y. y and 35 lie on a straight line and sum to 180°, that is

y + y + 35 = 180

2y + 35 = 180 ( subtract 35 from both sides )

2y = 145 ( divide both sides by 2 )

y = 72.5

7 0

3 years ago

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