Final answer:
Shilpa makes a profit of 12.5% by selling the pencils for ₹ 1.80 each which she bought for ₹ 1.60 each.
Step-by-step explanation:
Shilpa buys pencils at the rate of 15 for ₹ 24 and sells them at the rate of 10 for ₹ 18. To calculate her gain or loss percentage, we need to first determine the cost price and the selling price per unit.
The cost price per pencil is ₹ 24/15, which simplifies to ₹ 1.60 per pencil. The selling price per pencil is ₹ 18/10, which is ₹ 1.80 per pencil.
Now, we find the profit per pencil by subtracting the cost price from the selling price, which translates to ₹ 1.80 - ₹ 1.60 = ₹ 0.20 per pencil.
To find the profit percentage, we use the formula: (Profit per pencil / Cost price per pencil) × 100.
Substituting the known values gives us (₹ 0.20 / ₹ 1.60) × 100, which equals 12.5%. So Shilpa makes a profit of 12.5% on the pencils.