Answer:
Explanation:
Experiments were performed for 240 people, 60 people test positive.
Step 1: we calculate the sample proportion; p= 60/240= 0.25.
Step 2: calculate the standard error for the sample, which is the square root of sample proportion,p = p(1-p)/n, n=100
0.25(1-0.25)/100
= 0.04.
Step 3: calculate the test statistics; assuming the hypothesis test percentage is 25%
Then, we say 0.25-1=0.75
-0.75/0.04
= -1.875.
In particular, the sample results are -1.875 standard error.
Probability of Z is less than -1.875.
Look up it value in the Z table
