Q.A list price of ₹2,500 is sold for a net price of ₹2,125 after a trade discount. Find the rate of discount allowed.

Find the discount amount first, then express it as a percentage of the list price.

Discount amount $=2{,}500-2{,}125=375$. …

Here $L=₹2{,}500$ and $N=₹2{,}125$; the discount rate $d$ is unknown.

Step 1 — Find the discount amount.

Step 2 — Express this as a percentage of the list price.

$d = \frac{375}{2{,}500}\times100 = 15$ …

Expressing the discount amount as a percentage of the NET price ($375/2{,}125\times100\approx17.65\%$) instead of the LIST price is a common inversion — a discount rate is always defined relative …