A student claims that more than 55% of the mothers with school-age children worked outside the home. The student finds that a sample of 150 mothers from Bronx New York revealed that 96 were working outside the home. At a significance level of = 0.05, is the student correct?

Respuesta :

Answer:

There is sufficient evidence that the students claim is correct.

Step-by-step explanation:

From the information given:

The population proportion P = 55% = 0.55

The sample size n = 150

The sample mean x = 96

The sampling proportion from the sample mean [tex]\hat p = \dfrac{x}{n}[/tex]

[tex]\hat p = \dfrac{96}{150}[/tex]

[tex]\hat p =0.64\\[/tex]

The null and alternative hypothesis is:

[tex]H_o : p = 0.55 \\ \\ H_1 : p > 0.55[/tex]

The test statistics can be computed as follows:

[tex]Z = \dfrac{\hat p - p}{\sqrt{\dfrac{p(1-p)}{n}}}[/tex]

[tex]Z = \dfrac{0.64 - 0.55}{\sqrt{\dfrac{0.55(1-0.55)}{150}}}[/tex]

[tex]Z = \dfrac{0.09}{\sqrt{\dfrac{0.2475}{150}}}[/tex]

[tex]Z = \dfrac{0.09}{\sqrt{0.00165}}[/tex]

Z = 2.22

The P - value = P ( Z > 2.22)

= 1  - P( Z < 2.22)

= 1 - 0.98679

= 0.01321

Since P-value is less than the level of significance ∝ = 0.05

We reject the null hypothesis [tex]H_o[/tex]

Conclusion: There is sufficient evidence that the students claim is correct.