Question

A boat whose speed is 9km/h in still water ,gives 15km downstream qnd comes back in a total time of 3 hrs 45min. Find the speed of the stream. This question is from Quadratic equation. plzz solve fast i will mark brainlist

Answer 1

hey friend!!!!!

your answer is "3km/hr"
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Explaination=>
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T = time for downstream,

t = time for upstream travel.

T + t = 3 hrs 45 min = 15/4 hrs.

For downstream,

distance/velocity = time,

15/(V + v) = T

15/(9 + v) = T ... (1)

Similarly,

15/(9 - v) = t ... (2) .

..where V - Speed of boat,

v - speed of stream.

Add (1) and (2)

15/(9 + v) + 15/(9 - v) = T + t

15(18)/(81 - v2) = 15/4

v² = 81 - (18x4) = 9

v = sped of stream is 3 km/hr.___answer


hope it will help you