Question

Seven 1-centimeter buttons are stitched on a shirt.What area do all seven buttons cover? Round to the nearest hundredth. (Use 3.14 for π.)

Answer 1

The problem did not state if the 1cm measure is the radius or diameter. 

Area of a circle = π r²

Assuming: 1 cm is the radius

Area of 1 button = 3.14 * (1cm)² = 3.14cm²
Total area = 3.14cm² * 7 buttons =  21.98 cm²

Assuming: 1cm is the diameter : radius is 1/2 = 0.50cm
Area of 1 button = 3.14 * (1/2cm)² = 3.14 * 0.25cm² = 0.785cm²
Total area = 0.785cm² * 7 buttons = 5.495cm²