Question

Alicia rows 7 miles downstream in the same time she rows 3 miles upstream. She rows downstream 3 miles per hour faster then she rows upstream. Find the rowing rate for each way.

Answer 1

lets say let t = time taken for her to row in the river
x = downstream speed/hr
y = upstream speed/hr
so we have:
distance = time * velocity
7 = t*x
3 = t*y
x = 3+y

solve now for x, y, t
t = 3/y ; y= 3/t
t = 7/x ; x = 7/t
7/t = 3 + 3/t
7 = 3t + 3
3t = 4
t = 4/3
y = 3/(4/3) = 9/4 miles/hr
x = 7/(4/3) = 21/4 miles/hr

Answer 2

thankyou!!! so downstream speed is 21 divided by 4 orrrrr am i wrong?