### Query Detail : RBI Assistant Prelims

**a boat can cover a distance of 7.2km downstream and 3.2 km upstream in 2 hours. It can also cover 1.5 km downstream and 0.6 km upstream in 24 minutes. what is the speed of the boat when going downstream?**

pooja,
January 29th 2020,

RBI Assistant Prelims

**
**

**Let Speed of downstream = x & that of upstream = y**

So 7.2/x + 3.2/y = 2 ---(1)

and 1.5/x + 0.6/y = 24/60 ---(2)

LCM of 7.2 and 1.5 = 36 So multiplying (1) by 5 and multiplying (2) by 24, we will get,

36/x + 16/y = 10 ---(3)

36/x + 14.4/y = 9.6 ---(4)

Subtracting (4) from (3), we will get,

1.6/y = 0.4

y = 4

and by putting value of y in (1), we will get x = 6

So Speed of boat in downstream = 6kmph