Question

In an envelope there are some $5$ rupee notes and some $10$ rupee notes. Total amount of these notes together is $350$ rupees. Number of $5$ rupee notes are greater by $10$ than number of $10$ rupee notes. Then find the number of $5$ rupee and $10$ rupee notes.

Answer 1

Let the number of $Rs5$ notes be $x$ and the number of $Rs10$ notes be $y$
Given condition $5x+10y=350$
$\Rightarrow x+2y=70$ .....I
and also number of $5$ rupee notes are greater by $10$ than number of $10$ rupee notes
So, $x-y=10$
$\Rightarrow x=10+y$ .....(II)
From (I) and (II) we have
$10+y+2y=70$
$\Rightarrow 10+3y=70$
$\Rightarrow 3y=60$
$\therefore y=20$
$\therefore x=10+20=30$
Hence, the number of $Rs5$ notes $=30$, number of $Rs10$ notes $=20$