The time taken by a boat to travel 13 km downstream is the same as time taken by it to travel 7 km upstream. If the speed of the stream is 3 km/h, then how much time (in hours) will it take to travel a distance of 44.8 km in still water? |
$4 \frac{12}{25}$ $5 \frac{3}{5}$ $5 \frac{2}{5}$ $4 \frac{13}{25}$ |
$4 \frac{12}{25}$ |
Speed of the stream = 3 km/hr Let speed of the boat be y km/hr Time = \(\frac{ Distance }{ Speed }\) According to the question \(\frac{ 13}{ (y + 3) }\) = \(\frac{ 7}{ (y - 3) }\) = 13 (y – 3) = 7 (y + 3) = 13y – 39 = 7y + 21 = 13y – 7y = 21 + 39 = 6y = 60 = y = 10 So, speed of boat = 10 km/hr Time taken to cover 44.8 km distance in still water = \(\frac{ 44.8}{ (10) }\) = $4 \frac{12}{25}$ |