Question

A 2020 Pew Research poll found that 65% of U.S. adults believe that President Donald Trump was too slow to make major steps to stop the spread of the coronavirus. Let's assume that 0.65 is the population proportion. Suppose random samples of 100 U.S. adults are randomly selected, and the proportion of each sample is found.

Suppose you find a sample of 100 adults in which 62% believe that President Donald Trump was too slow to make major steps to stop the spread of the coronavirus. What is the Z-score of this sample proportion? Round the value to 2 decimal places.

Answer 1

$Z=\frac{\hat{p}-p}{\sqrt{\frac{pq}{n}}}= \frac{ 0.62 - 0.65 }{\sqrt{\frac{ 0.65 * 0.35 }{ 100 }}}= -0.63$