Answer:the length of plan A workout is 1.5 hours.
the length of plan B workout is 1.25 hour.
Explanation:
Let x represent the length of plan A workout.
Let y represent the length of plan B workout.
On Wednesday there were 8 clients who did Plan A and 4 who did Plan B. Hans trained his Wednesday clients for a total of 17 hours. This means that
8x + 4y = 17 - - - - - - - - - -1
On Thursday there were 3 clients who did Plan A and 2 who did Plan B. Hans trained his Thursday clients for a total of 7 hours. This means that
3x + 2y = 7 - - - - - - - - - - - - - 2
Multiplying equation 1 by 3 and equation 2 by 8, it becomes
24x + 12y = 51
24x + 16y = 56
Subtracting, it becomes
4y = 5
y = 5/4 = 1.25 hours
Substituting y = 1.25 into equation 2, it becomes
3x + 2 × 1.25 = 7
3x + 2.5 = 7
3x = 7 - 2.5 = 4.5
x = 4.5/3 = 1.5