Question

A purse has only two-rupee and five rupee coins. The sum of the coins is $36$ and the total value of the coins is $Rs.84$. Find the number of five-rupee coins.

Answer 1

Let x be no. of two rupee coins and y be no. of five rupee coins.

Given that,

$x+y=\mathrm{36...}\left(1\right)$

$2x+5y=\mathrm{84...}\left(2\right)$

$\left(1\right)\times 5\Rightarrow$ $5x+5y=180$

$2x+5y=84$

$3x=180-84$

$\Rightarrow x=60.28$

$\Rightarrow x=32;y=36-32=4$

Therefore no. of five rupee coins are 4.