Question

A boat covers 18 km downstream in 3 hours . If speed of current is `33 (1)/(3)`% of its downstream speed . In what time will it cover a distance of 50 km upstream ?
A. 50 hour
B. 40 hour
C. 30 hour
D. 25 hour

Answer 1

Correct Answer - D
According to question ,
Downstream speed = `(18)/(3)` = 6 km/hr
or x + y = 6 (when `x to` speed of boat in still water ,
`y to` speed of current )
Speed of current = `(1)/(3) xx 6 = 2` km/hr
Speed of boat in still water = 4 km/hr
Required time = `(50)/((4-2)) = 25` hour