Question

Last week jean did two sit ups on monday and three sit ups on Wednesday. This week, jean did three times as many as last week. How many sit ups did jean do this week?

Answer 1

2 on mon. plus 3 on wed. is 5. 3 x 5 is 

15 sit ups

Answer 2

If he did 2 on Monday and 3 on Wednesday he did 5 total. If he did 3 times that multiply 5 by 3 to get 15. So he did 15 sit-ups this week.
2+3=5 5*3=15