Maria the trainer has two solo workout plans that she offers her clients

Question

Maria the trainer has two solo workout plans that she offers her clients: Plan A and Plan B. Each client does either one or the other (not both). On Friday there were 3

 clients who did Plan A and 8

 who did Plan B. On Saturday there were 5

 clients who did Plan A and 2

 who did Plan B. Maria trained her Friday clients for a total of 15

 hours and her Saturday clients for a total of 8

 hours. How long does each of the workout plans last? 

LengthofeachPlanAworkout:hour(s)

LengthofeachPlanBworkout:hour(s)

Answer 1

Friday: 3A +8B= 15

Saturday: 5A+2B = 8

20A+8B = 32

3A +8B =15

17A = 17

A = one hour on Plan A

B = (15-3)/8 = 12/8 = 1 1/2 hours on Plan B