Question

How do I know when to subtract or add or divide when it comes to the end of the solution?

Answer 1

Given a rectangular peice of paper

Length = 34 cm

Width = 16 cm

So, the area of the rectangle = 34 x 16 = 544 cm²

Two semicircles cut out of it

The diameter of the circle = d = 16 cm

So, the radius of the circle = r = d/2 = 8 cm

The area of the two semicircles = area of the complete circle

so, the area of the circle = πr² = 3.14 x 8² = 200.96 cm²

So, the area of the remaining paper = area of the rectangle - area of the circle

= 544 - 200.96 = 343.04 cm²

So, the answer will be Area = 343.04 cm²