In a test for equality of two proportions, the sample proportions were p₁ = 12/50 and p₂ = 18/50. The pooled proportion is: A).20 B).24 C).36 D).30

Question

Quizplus · Accepted Answer

The formula to calculate the pooled proportion is: 
pooled proportion = (x1+x2)/(n1+n2)
where x1 and x2 are the number of successes in samples 1 and 2 respectively, and n1 and n2 are the sample sizes for samples 1 and 2 respectively. 
Plugging in the values, we get: 
pooled proportion = (12+18)/(50+50) = 30/100 = 0.30
Therefore, the answer is D, with a pooled proportion of 0.30.

In a Test for Equality of Two Proportions, the Sample