Given the diameter of the circle, find the area of the circle: 1) d = 10cm; 2) d = 30cm; 3) d = 100cm; 4) d = 12m

1) 10 divided by 2 times 3.14 = 15.7 2) 30 divided by 2 times 3.14 = 47.1 3) 100 divided by 2 times 3.14 = 157 4) 12 divided by 2 times 3.14 = 18.84

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