You have 89 minutes to take an exam of 33 questions.

Question

You have 89 minutes to take an exam of 33 questions.After you finish the first 12 questions you realize you must answer the remaining questions twice as fast to finish the exam..How many questions per minute were you answering?

Answer 1

m = minutes spent on each of the first 12 questions

m/2 = minutes spent on each of the last 21 questions (twice as fast means in half the time)

 

12m = time spent on the first part

21m/2 = time spent on the second part

 

12m + 21m/2 = 89

24m + 21m = 178

45m = 178

m = 3.95

 

In the first section you answered 12 questions in 47.5 minutes, or 0.25 questions per minute

 

In the second section you answered 21 questions in 41.4 minutes, or 0.51 questions per minute