Answer:
1/2 or 0.5 hours
Step-by-step explanation:
r = time for repairman to fix one pair of shoes.
a = time for assistant to fix one pair of shoes.
a = r×1.5
x×r + y×a = 6
x = number of pairs of shoes repaired by repairman.
y = number of pairs of shoes repaired by assistant.
x+y = 10
y = 10-x
x = y×1.5 (based on the a/r ratio : as the assistant needs 1.5 times longer, the repairman will have repaired 1.5 times more pair of shoes in the same time)
y = 10 - y×1.5
y + y×1.5 = 10
2.5×y = 10
y = 4
=> x = 6
6×r + 4×r×1.5 = 6
6×r + 6×r = 6
12×r = 6
r = 6/12 = 1/2 or 0.5 hours
