Question

How many bricks 20 cm long and 10 cm wide will be require to pave a floor 10 m long and 8m long?

Answer 1

no. of bricks
$= \frac{1000 \times 800}{20 \times 10 } \\ = 4000$

Answer 2

firstly convert meter into centimeters
that is 10m=1000cm
and 8m=800cm.
area of floor 800X1000=800000cm
length of brick 20cm breadth of brick 10cm
now area of brick will be 20X10=200cm
800000÷200(ar of floor / ar of brick)
you can also convert it into meters by dividing by 100
800000÷100=8000
200÷100=2
here 8000÷ 2
4000
you need 4000 bricks