Find the area and round to the nearest tenth: Diameter equals 5 1/2 yards

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

Larquita is writing a book for her job, where she works the same number

ryzh [129]

so what u gotta do in this add and multiply everything up like monday she worked before and wor and during work, then tuesday she worked twice as much as monday then u gotta add and multiply everythin up, same thing all over again, then you get ur answer, nlow this app is too help you, i helped you, im not goona give ur answer, ur gonna give the answer to ur selfe, now i dont have time rn to answer it and if i did i would help you n answer but u gotta do ur work, have a great daay!

3 0

3 years ago

Y=log x If y=10, then what is x?

netineya [11]

Answer:

First question, x= 10^10.

Second question is 10!. or 362880

Step-by-step explanation:

First Question:

Simple logx has a base of 10, i.e log10 x,

the question will be 10 = log10 x,

when taking the base "10" from the right side to the left, the number on the left side becomes the power of the base, in this case 10 from the right will be base and 10 from the left will power and log will vanish.

x=10^10.

Another example with different numbers

Y=logx if Y= 12, What is x?

The base is ten when not given,so:

12=logx

10^12=x

Second Question;

simple multiplication just multiply the numbers.

10! is pronounced as 10 factorial,

5! will be 5x4x3x2x1=120

8 0

4 years ago

Convert 7/66 to a decimal equivalent

wlad13 [49]

$\frac{7}{66}$ = 0.10606

Step-by-step explanation:

$\frac{7}{66}$

Since we have only one digit in the numerator and the denominator has 2 digits, we have to 0 along with 7, so that it becomes 70, 1 time 66 is 66, 70 - 66 = 4 is the remainder, so the quotient is 0.1, then along with 4 we have to add one 0 , so it becomes 40 which is lesser than 66 so one more 0 is added and then it becomes 400, 6 times 66 is 396, 400 - 396 = 4 again the process going on. The quotient is 0.10606...

4 0

3 years ago

I need help for the 5th time

Leviafan [203]

Answer:

3.2t - 2.4

Step-by-step explanation:

Given

- 3.6 - 1.9t + 1.2 + 5.1t ← collect like terms

= (- 1.9t + 5.1t) + (- 3.6 + 1.2)

= 3.2t + (- 2.4)

= 3.2t - 2.4

8 0

3 years ago