Adining hall measuring 10m long and 8m wide overlaid with nine circular carpets. the diameter of one carpet is 200cm. calculate the area in square meters, floor area of the board that is not covered by the carpet.

We know that
area of dining hall=10*8> 80 m²

area of one circular carpet=pi*r²
diameter=200 cm> 2 m
r=2/2> 1 m
area of one circular carpet=pi*1²> 3.14 m²
area of nine circular carpet=9*3.14> 28.26 m²

the floor area of the board that is not covered by the carpet=80-28.26
the floor area of the board that is not covered by the carpet=51.74 m²

the answer is
51.74 m²

I'm sure the answer is a