in Quantitative Aptitude recategorized by
414 views
0 votes
0 votes

A man rowed $3$ miles upstream in $90$ minutes. If the river flowed with a current of $2$ miles per hour, how long did the man’s return trip take?

  1. $20$ minutes
  2. $30$ minutes
  3. $45$ minutes
  4. $60$ minutes
in Quantitative Aptitude recategorized by
12.6k points
414 views

1 comment

30minutes
0
0

1 Answer

0 votes
0 votes

Ans is option (B)

Let the speed of the boat be $v$ miles per hour.

While going upstream, river current opposes the boat’s motion. So, the effective speed of the boat would be $(v-2)$ miles per hour.

$\therefore$  $1.5=\frac{3}{v-2}$   $\Rightarrow$   $v=4$ miles per hour.

While going downstream, river current supoorts boat motion. So, the effective speed of the boat would be  $(v+2)=4+2=6$ miles per hour.

$\therefore$  time taken for the downstream trip  $=$  $\frac{3}{6}=0.5$ hours $=$ $30$ minutes

658 points

Related questions

Quick search syntax
tags tag:apple
author user:martin
title title:apple
content content:apple
exclude -tag:apple
force match +apple
views views:100
score score:10
answers answers:2
is accepted isaccepted:true
is closed isclosed:true