A newspaper poll asked respondents if they trusted "eco friendly" labels on
Cleaning products. Out of 1000 adults surveyed, 498 responded "yes." We would like to
Test if the proportion of respondents that trust these labels is at least 50%. The calculated
Test statistic value is
A) -.126
B) -2.45
C) 1.27
D) -1.89
E) .139

Question

Quizplus · Accepted Answer

The test statistic is calculated using the formula for a proportion z-test: $ z = \frac{\hat{p} - p_0}{\sqrt{\frac{p_0(1-p_0)}{n}}} $. Here, $\hat{p} = \frac{498}{1000} = 0.498$, $p_0 = 0.5$, and $n = 1000$. Plugging these into the formula gives a z-value of approximately -0.126.

A Newspaper Poll Asked Respondents If They Trusted "Eco Friendly