the speed of a boat in still water is 15 kilometre per hour and the speed of the stream is 5 kilometre per hour find the time taken by the boat to cover 40 upstream and. 36 downstream (answer is 1 h 48 min ))
Answers
Answered by
0
Answer:
Speed of the stream =5 km/hr.
Step-by-step explanation:
Given :
Speed of boat in still water =15 km/hr
Let x be speed of the stream in km/hr
Speed of the boat upstream =15−x
Speed of the boat down stream =15+x
Time taken for upstream T 1 = 30/15-x
Time taken for downstream T 2 = 30/15+x
given,
T1 + T2 = 9/2
(30 / 15-x) + (30 / 15+x) = 9/2
(30*30) / (225 - x^2) = 9/2
100 / 225-x^2 = 1/2
225 - x^2 = 200
x^2 =25
therefore; x = 5
x = 5 km/hr
Speed of the stream =5 km/hr.
DEAR FRIENDS, PLEASE MARK MY ANSWER AS THE BRAINLIEST
Similar questions