If a boat goes 72 miles downstream in 3 hrs and upstream 60 miles in 6 hours , what is the rate of the river and the boat in still water respectively?

What type of wizardry is this?

What type of wizardry is this?

S=speed of the boat
C=current
Speed upstream = (s-c)
Speed downstream = (s+c)
Distance=time*speed
3(s+c)=72
s+c=24
6(s-c)=60
s-c=10

Use the elimination process to solve the system of equations
s+c=24; s-c=10
2s=34
s=17 mph boat speed

Find the current:
s+c=24
17+c=24
c=24-17
c=7

Check your solutions: 3(s+c)=72 and 6(s-c)=60
3(24)=72
6(10)=60

S=speed of the boat
C=current
Speed upstream = (s-c)
Speed downstream = (s+c)
Distance=time*speed
3(s+c)=72
s+c=24
6(s-c)=60
s-c=10

Use the elimination process to solve the system of equations
s+c=24; s-c=10
2s=34
s=17 mph boat speed

Find the current:
s+c=24
17+c=24
c=24-17
c=7

Check your solutions: 3(s+c)=72 and 6(s-c)=60
3(24)=72
6(10)=60

Ive seen this before! the answer is b