Question

250 boxes of dimensions 30cm×20cm×20cm are required for packing some books . How much cardboard will have to be use for the same.​

Answer 1

Dimensions of box =

30cm×20cm×20cm

Surface area of 1 box =

2(lb + bh + lh)

=2 (30×20+20×20+20×30)

=2 (600+400+600)

=2 (1600)

=3200cm2

Surface area of 250 boxes =

250×3200

=800000cm2

Answer 2

volume of one box=(30×20×20)cm=12000 cm3
250boxes=12000×250=3000000cm3=3m3
hence 3m3 cardboard is required