Question

Seeta Devi has $Rs9$ in fifty-paise and twenty five-paise coins. How many coin of each kind does she have ?

Answer 1

Let the number of $25$ paise coins =x
and the number of $50$ paise coins=y
ATQ
$25x+50y=900$
and,$x=2y$
$25\left(2y\right)+50y=900$
$y=9$
$x=18$
number of $25$ paise coins=$18$
number of $50$ paise copins$=9$