Question

A courtyard 20 m long and 15 m broad is to be paved with bricks of length
25 cm and breadth 12 cm. Find the number of bricks required. Use units of cm , m etc .
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Answer 1

length of the rectangular Courtyard = 20m 16 cm = 2016 cm

Breadth of the rectangular Courtyard = 15m 60 cm = 1560 cm

HCF(2016, 1560) =?

Prime factorisation of 2016 and 1560 are as follows:

2016 = 2 × 2 ×2 ×2 ×2 ×3 ×3 ×7

1560 = 2 × 2 ×2 ×3 ×5 ×13

→HCF(2016, 1560) = 2 × 2 ×2 ×3 = 24

Least possible number of stones to be paved

= Area of a rectangular courtyard ÷ Area of a square stone

= (2016 × 1560) ÷ (24)2

= 5460