Question

Amita wants to make rectangular cards measuring 8 cm × 5 cm. She has a square chart paper of side 60 cm. How many complete cards can she make from this chart? What area of the chart paper will be left?

Answer 1

The square chart of length 60 cm can be divided exactly in 7 parts each of length 8 cm along one side of chart paper and exactly in 12 parts each of length 5 cm along other side of chart paper.

The figure shows that the number of rectangular cards which can be made from the square chart paper is 7 × 12 = 84

Now, area of the square chart paper

= (60 × 60) cm² 

= 3600 cm²

Area of one rectangular card

= (8 × 5) cm²

= 40 cm²

∴ Area of 84 rectangular cards

= 84 × 40 cm² 

= 3360 cm²

∴ Area of remaining chart paper

= (3600 – 3360) cm² 

= 240 cm²