Question

A mancan row 14 km/h in still water.In the stream flowing with the speed of 10 km/h he tales 4 hours to move with the stream and come back. Find the distance he rowed the boat

Answer 1

Answer:

27.43 km

Explanation:

Let the distance travelled in one direction = X

Total distance travelled = 2X

Speed of manacan in still water Vm = 14 km/h

Speed of the stream Vs = 10 km/h

∴ When rawing downstream, speed of boat Vd = Vs + Vm

∴ Vd = 10 + 14

∴ Vd = 24 km/hr ....(1)

Speed of bat upstream against current Vu = Vm - Vs

∴ Vu = 14 - 10

∴ Vu = 4 km/hr ... (2)

Time taken to row with flow Td = Distance travelled ÷ Speed

∴ Td = X ÷ Vd

∴ Td = X / 24  hr ..(3)

Time taken to row against stream Tu = Distance ÷ Vu

∴ Tu = X / 4 hrs  ...(4)

Total time taken is given as 4 hours

∴ Td + Tu = 4

∴ X/24 + X/4 = 4

∴ (X + 6X) / 24 = 4

∴ 7X = 96

∴ X = 96 / 7 km

∴ Total distance rowed = 2X = 2 * 96 / 7

∴ Total distance rowed = 27.43 km

Answer 2

Answer:

27.43km

Explanation:-

1. given that: - speed of mancan row in still water = 14km/h.
2. stream flowing speed = 10km/h.
3. total time spent move mancan and come = 4hr.

now , we have according to question:-

• mancan row speed with flowing stream(V) = 10+14 = 24km/h
• mancan row speed opposite to flowing stream(u) = 14 -10 = 4km/hr.

let going distance = S , and coming distance = S

total distance = 2S.

• here, going time (T1) = S/24 hr.
• coming time (T2) = S/4 hr.

TOTAL TIME :-

• 4 = T1+T2
• 4 = s/24 + S/4
• 4 = (S+6S)24
• 7S = 96
• S = 96/7
• here,
• 2S = 96/7
• 2S= 192/7 = 27.43

total rowed distance = 2S =( 27.43)km

i have its help.