Estimation in Percentages

Your bill in a shop is ₹ 577.80 and the shopkeeper gives a discount of 15%. How would you estimate the amount to be paid ?

Instructions

Round off the bill to the nearest tens of ₹ 577.80, i.e., to ₹ .

Find 10% of this i.e., ₹ × 580 = ₹ .

Take half of this, i.e., 12 × 58 = ₹

Add the amounts in (ii) and (iii) to get ₹ .

You could therefore reduce your bill amount by ₹ 87 or by about ₹ 85, which will be ₹ approximately.

Instructions

Try estimating 20% of the same bill amount.

Finding 20% of ₹577.80: × 577.80 =

Subtracting the discount from the bill: Amount tot be paid = 577.80 - 115.56 =

Thus, the amount to be paid becomes ₹ 462.24.

Try finding 15% of ₹ 375.

Finding 15% of ₹ 375: 15% of 375 = × =

So, 15% of ₹375 is ₹56.25.

Chapter 5: Comparing Quantities using Proportion