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

Let ABCD be square chart of side 60 cm.

Cut out rectangular cards measuring 8 cm × 5 cm

Now if we cut along AB then we can cut 12 rectangular cards.

So we can cut 7 rows with 12 rectangular cards each

Area of cut outs of rectangular cards = 7 × 12 × 8 × 5

= 3360 sq.cm

Area of left part = 4 × 60

= 240 sq.cm