A bicycle was sold for ₹4830 at a profit of 15%. Find its cost price.

A 15% profit means the SP is 115% of the CP: $\frac{115}{100}\times \text{CP}=4830$, so CP = $\frac{4830\times 100}{115}=₹4200$. Check: 15% of 4200 = 630, and 4200 + 630 = 4830. ₹4105.50 takes 15% off the ₹4830 — but the 15% was calculated on the cost price, so it is a smaller amount than 15% of the SP. ₹5554.50 adds a profit instead of removing one, and ₹32200 divides by 15 rather than 115.