On Monday afternoon, Andrew rowed his boat with current for 4.5 hours and covered 27 miles, stopping in the evening at a campground. On Tuesday morning he returned to his starting point against the current in 6.75 hours. Find the speed of the current and the rate at which Andrew rowed in still water. (I have problems solving word problems)

Answer 1

speed down = (v+c)
time down =4.5 = 27/(v+c)

speed up = (v-c)
time up = 6.75 = 27/(v-c)

so
6.75(v-c) = 4.5(v+c)
6.75 v -4.5 v = 4.5 c + 6.75 c
2.25 v = 11.25 c
v = 5 c
now back
6.75 = 27/(5c-c) = 27/4c
27 = 27c
c = 1

Answer 2

What is V+C