Question

Claim: Fewer than % of adults have a cell phone. In a reputable poll of adults, % said that they have a cell phone. Find the value of the test statistic.

Answer 1

The question asks for z( test statistic). For this is necessary to apply the equation?

The text of the question gives:

null hypothesis (p)= 0.93

alternative hypothesis

n= number of adults =1124

Now, you should replace the values in the equation for z.

$z=\frac{0.87-0.93}{\sqrt[]{\frac{0.93\cdot(1-0.93)}{1124}}}=-\frac{0.12\sqrt{18.2931}}{0.0651}=-7.88$