Answer:
Darren must correct 900 problems each week.
Explanation:
Darren teaches a class of 25 students.
He assigns homework 3 times a week, and each assignment consists of 12 problems.
Darren gives homework for one student in a week = 12 × 3 =36 problems
Darren must correct problems each week = 36 × 25 = 900 problems
Darren must correct 900 problems each week.