If it is assumed that 80 percent of those who receive a questionnaire by mail will respond and 300 responses are needed, what is the minimum number of questionnaires that should be mailed? Choose one
A) 375 B) 420 C) 480 D) 500 E) 600

Rationale: "minimum no of mail to be sent for getting 300 responses at 80 % = 300 / 0.8 = 375 option a"
Answer: A