The value of the test statistic is?

Question

The claim is that the proportion of peas with yellow pods is equal to 0.25 (or 25%). The sample statistics from one experiment include 400 peas with 82 of them having yellow pods. Find the value of the test statistic.

 

Round decimal as needed

Answer 1

p = 0.25

q = 1 - p = 0.75

 

x = 82

n = 400

 

p_sample = x/n = 82/400 = 0.205

 

test statistic,  z = (p_sample - p) / sqrt(pq/n) = (0.205 - 0.25) / sqrt(0.25×0.75/400) = -2.078