Answer:
rate of boat in still water = 40 mph
rate of current = 10 mph
Explanation:
speed of boat in still water = s
speed of current = c
speed upstream = s - c
speed downstream = s + c
time going upstream = 5 hours
time going downstream = 3 hours
distance = 150 miles
speed = distance/time
s = d/t
d = st
upstream:
d = st
150 = (s - c)(5)
s - c = 30 Eq. 1
downstream:
d = st
150 = (s + c)(3)
s + c = 50 Eq. 2
System of equations:
Equations 1 and 2 for a system of equations.
s - c = 30
s + c = 50
Add the equations and solve for s.
2s = 80
s = 40
Substitute 40 for s in Eq. 2 and solve for c.
s + c = 50
40 + c = 50
c = 10
Answer:
rate of boat in still water = 40 mph
rate of current = 10 mph