find the distance traveled by a boat that went downstream 5hrs and upstream 9hrs at a speed of 8kph?

Answer 1

There is info missing. We do not know the speed of the river itself.

Secondly, do you mean 8 knots? If kph means knots per hour it is an acceleration unit which is also inconsistant.

I can assume that the boat started and ended at the same location but we are not advised to do this. If I make this assumption, and the boat's speed is 8 knots relative to water (and not including the increase or decrease relative to ground associated with river current), we have the following

1. Distance traveled down stream = x miles
2. Time to travel x miles down = 5 hours
3. 5 hr (8 + s) = x miles where s = river speed.
4. distance traveled upstream = x miles
5 time to travel x miles up = 9 hr
6. 9 hr (8-s)=x

or 9(8-s) = 5(8+s)
72 - 9s = 40 +5s
32 = 14 s
s = 32/14 knots

The distance traveled down then is
5(8 + 32/14) which is the distance traveled up also

Therefore total distance traveled up and down is
2*5(8 +32/14)

This is based upon my assumptions above; I am reading into the problem but the info as provided is not sufficient as provided.

Answer 2

Your question is not totally clear. I'm assuming you are interested in the boat's final position. If downstream is negative and upstream is positive, the boat traveled (-5 + 9) = 4 hours, a positive value indicating upstream travel, and (4 hr)(8 km/hr) = 32 km. If you actually mean total path length, it's (5 hr + 9 hr)(8 km/hr) = (14 hr)(8 km/hr) = 112 km.

Answer 3

Another math question in the geography section!