Question

By selling $130$ cassettes, a man gains an amount equal to the selling price of $5$ cassettes. Find the gain percent.

Answer 1

Let the price of cassette be $Rs.x$
Selling price of of $5$ cassettes $=5x$
Selling price of $130$ cassettes $=130x$
Since, gain amount is $=$ SP of $5$ cassettes.
Thus, gain amount$=5x$
So, cost price$=$Total SP$-$Gain
Thus, CP$=130x-5x=125x$
$\%=\frac{\text{Gain}}{\text{CP}}\times 100$
$=\frac{5x}{125x}\times 100$
$=4\%$
Therefore, the gain percent is $4\%$.