Distance

Algebra Level pending

A boy rows downstream at the rate of $5$ miles per hour and upstream at the rate of $2$ miles per hour. How far downstream should he go if he is to return $1.4$ hours after leaving? Give your answer in miles.

The answer is 2.

1 solution

A Former Brilliant Member
May 14, 2017

from $V=\dfrac{d}{t}$ , where $V=speed$ , $d=distance$ and $t=time$ we get $t=\dfrac{d}{V}$

$t_D+t_U=1.4$

$\dfrac{d}{5}+\dfrac{d}{2}=1.4$ , multiplying both sides by $10$ , we get

$2d+5d=1.4$

$d=2~miles$

Distance

The answer is 2.

1 solution

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