Question 27194
20 minutes = 1/3 hours.
30 minutes = 1/2 hours.
Let the speed of the boat be y.
Let the speed of the current be x.



{{{8/(x-y)/3=8/(x+y)/2}}}
{{{(x+y)/2=8}}} ---> solve for y
x-y=16
y=16+x (subsitution)


(x+y)/2=8
x+y=24 (subsitue for y)
x+(16+x)=24
x+16+x=24
2x=8
x=4

y=16+4
y=20


Hence, the speed of the boat is 20mph and the speed of the current is 4mph.