The largest possible circle is cut from a square sheet of side 28 cm. What is the area of the leftover sheet, in square cm? (Use π = 22/7.)

The largest circle has diameter 28 cm, so $r=14$ cm and its area = $(22/7)\times 196=616$ sq cm. The sheet is $28^2=784$ sq cm, so the leftover = 784 - 616 = 168 sq cm. The trap 616 reports the piece cut out rather than what remains; 784 is the whole sheet; 696 subtracts the circle's CIRCUMFERENCE of 88 cm instead of its area, mixing a length into an area.