Suppose a poll is taken that shows that 281 out of 500 randomly selected, independent people believe the rich should pay more taxes than they do. Test the hypothesis that a majority (more than 50%) believe the rich should pay more taxes than they do. Use a significance level of 0.05.

Respuesta :

Answer:

The claim is true.

Step-by-step explanation:

Given - Suppose a poll is taken that shows that 281 out of 500 randomly selected, independent people believe the rich should pay more taxes than they do.

To find - Test the hypothesis that a majority (more than 50%) believe the rich should pay more taxes than they do. Use a significance level of 0.05.

Solution -

Given that,

X = 281, n = 500

So,

The hypothesis are :

H0 : p = 0.50

H1 : p > 0.50

So,

Sample proportion is

p bar = X/n

         = 281/500

         = 0.562

⇒p bar = 0.562

Now,

Test statistics :

[tex]Z_{0} = \frac{p bar - p}{\sqrt{\frac{p(p - 1)}{n} } } \\= \frac{0.562 - 0.50}{\sqrt{\frac{0.50(0.50 - 1)}{500} } }\\= 0.277[/tex]

∴ we get

[tex]Z_{0} = 0.277[/tex]

SO,

p-value = P( Z ≥ 0.277)

             = 1 - P(Z ≤ 0.277)

             = 1 - 0.997

             = 0.002779

∴ we get

The conclusion is -

As [tex]Z_{0} = 0.277[/tex] > Z = 1.645

We reject H0

And

We have enough information to conclude that the population proportion is greater than 0.50

So,

The claim is true.