138k views
2 votes
A motorboat travels 106 kilometers in 2 hours going upstream. It travels 142 kilometers going downstream in the same amount of time. What is the rate of the boat in still water and what is the rate of the current?

User Kim HJ
by
8.1k points

1 Answer

4 votes

Explanation:

Rate UP stream = ( s - w) = 106 km / 2 hr

( where s = boat speed w = current speed )

(s-w) = 53 km/hr

Rate DOWNstream = ( s+w) = 142 / 2 = 71 kmhr

( s-w) + ( s+w) = 53 + 71 km/hr

2s = 124

s = 62 km /hr then s+w = 71 shows w = 9 km/hr

User Brage
by
7.9k points