Answer:
answer: the crews rowing rate is 6 mph and the rate of the current is 3 mph
Step-by-step explanation:
v the crew rowing rate
u rate of the current
downstream v + u = 13.5/1.5 = 9 mph
upstream v - u = 13.5/4.5 = 3 mph
u = 9 - v
v - ( 9 - v ) = 3
v - 9 + v = 3
2 v = 12
v 6 mph, u 9 - 6 = 3 mph