Suppose a university advertises that its average class size is 32 or less. A student organization is concerned that budget cuts have led to increased class sizes and would like to test this claim. A random sample of 40 classes was​ selected, and the average class size was found to be 34.8 students. Assume that the standard deviation for class size at the college is 99 students. Using α=0.10​, complete parts a and b below.a. Does the student organization have enough evidence to refute the​ college's claim?Determine the null and alternative hypotheses.Upper H 0H0​:μ▼Upper H 1H1​:μ▼

Respuesta :

Answer:

a

The  student does have enough evidence to refute the college claim

b

The null hypothesis is [tex]H_o : \mu \le 32[/tex]

The alternative hypothesis is [tex]H_a : \mu > 32[/tex]

Step-by-step explanation:

From the question we are told that

The average class size is [tex]\mu = 32[/tex]

The sample size is [tex]n = 40[/tex]

The sample mean is [tex]\= x = 34.8[/tex]

The standard deviation is [tex]\siigma = 99[/tex]

The significance level is [tex]\alpha = 0.10[/tex]

The null hypothesis is [tex]H_o : \mu \le 32[/tex]

The alternative hypothesis is [tex]H_a : \mu > 32[/tex]

Generally the test statistics is mathematically represented as

[tex]z =\frac{\= x - \mu}{ \frac{\sigma }{\sqrt{n} } }[/tex]

=> [tex]z = \frac{34.8 - 32}{ \frac{99 }{\sqrt{99} } }[/tex]

=> [tex]z = 0.1789 [/tex]

Generally the p-value is mathematically represented as

[tex]p- value = P (Z > 0.1789)[/tex]

From the z- table

[tex] P (Z > 0.1789) =0.42901 [/tex]

So

[tex]p- value = 0.42901 [/tex]

So from the calculation we can see that [tex]p- value > \alpha[/tex] so we fail to reject the null hypothesis

This means that the student does not have enough evidence to refute the college claim