Can anyone help me with this math problem

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

2 years ago

9876543210 number name in international system

vfiekz [6]

What exactly are you asking?
What’s the question?

7 0

2 years ago

Solve for x: 4(x + 2) = 3(x - 2)

Pani-rosa [81]

Answer:

x = -14

Step-by-step explanation:

Step 1: Write equation

4(x + 2) = 3(x - 2)

Step 2: Solve for x

Distribute: 4x + 8 = 3x - 6
Subtract 3x on both sides: x + 8 = -6
Subtract 8 on both sides: x = -14

Step 3: Check

Plug in x to verify it's a solution.

4(-14 + 2) = 3(-14 - 2)

4(-12) = 3(-16)

-48 = -48

7 0

2 years ago

Read 2 more answers

A rare mutation only occurs in 1 in every 2048 generations of fruit flies. We can assume that whether or not the mutation occurs

sergey [27]

Answer:

(A) 0.0244

(B) 1 (not 1.47 as is calculated) since probability values are between 0 and 1; 0 and 1 inclusive

Step-by-step explanation:

The rare mutation only occurs in 1 generation, out of every 2048 generations. This implies that the next occurrence will fall in or within the next 2048 generations (2 generations in 4096 generations, will have the rare mutation).

(A) The probability of occurrence of this mutation at least once (at most infinity) in 50 generations of fruit flies will surely be less than, as 50 is less than 2048.

The accurate probability is gotten when 50 is divided by 2048

50÷2048 = 0.0244

(B) The probability of seeing this mutation at least once (at most infinity) in 3000 generations would have been 1.47 but for 3 reasons;

- The full question already tells that the mutation will occur once in every 2048 generations and 3000 is greater than 2048, hence there will be a sure occurrence within 3000 generations.

- Question (b) asks you to calculate the probability of seeing this mutation at least once in 3000 generations so, the probability is 1 (representing full probability).

- In probability theory or statistics, all probability values fall within 0 and 1; with 0 representing no occurrence at all and 1 representing full occurrence.

5 0

3 years ago

Please help! this is a final! FUNCTIONS

Gnom [1K]

The zeroes are -1/2 and -2
last option

3 0

2 years ago