Consider to circular swimming pools. Pool A has a radius of 12 feet and Pool B has a diameter of 7.5 meters which pool has a greater circumference how much greater justify your answers

C = Pi * d where C = circumference, d = diameter, r = radius

C = 2*pi * r

we need to watch the units since they are different

Pool A

C = 2 * pi * r

C = 2 * pi * 12 = 24 * pi in feet

Pool B

C = pi * d

change meters to feet

7.5 m * 3.28 ft / 1 m = 24.6 ft

C = pi * 24.6 = 24.6 * pi in ft

Pool B had a greater circumference

24.6 * pi > 24 pi