To prepare for a party, Mark buys a small bunch of balloons for $4.00 and

Zappos is an online retailer based in Nevada and employs 1,300 employees. One of their competitors, Amazon, would like to test t

Amanda [17]

Answer:

$t=\frac{33.9-36}{\frac{4.1}{\sqrt{22}}}=-2.402$

$df = n-1= 22-1=21$

$t_{\alpha/2}= -2.08$

Since the calculated values is lower than the critical value we have enough evidence to reject the null hypothesis at the significance level of 2.5% and we can say that the true mean is lower than 36 years old

Step-by-step explanation:

Data given

$\bar X=33.9$ represent the sample mean

$s=4.1$ represent the sample standard deviation

$n=22$ sample size

$\mu_o =26$ represent the value that we want to test

$\alpha=0.025$ 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)

System of hypothesis

We need to conduct a hypothesis in order to check if the true mean is less than 36 years old, the system of hypothesis would be:

Null hypothesis: $\mu \geq 36$

Alternative hypothesis: $\mu < 36$

The statistic is given by:

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

And replacing we got:

$t=\frac{33.9-36}{\frac{4.1}{\sqrt{22}}}=-2.402$

Now we can calculate the critical value but first we need to find the degreed of freedom:

$df = n-1= 22-1=21$

So we need to find a critical value in the t distribution with df =21 who accumulates 0.025 of the area in the left and we got:

$t_{\alpha/2}= -2.08$

Since the calculated values is lower than the critical value we have enough evidence to reject the null hypothesis at the significance level of 2.5% and we can say that the true mean is lower than 36 years old

3 0

3 years ago

F(x) = -7x2 + 9x - 15 and g(x) = -12x2 – 15x + 7

djyliett [7]

Answer:

${5x}^{2} + 6x = - 8$