LESSON 7

Formulas with Pi

Keys:

x

EXP ►

Try this

1. Find the amount of border needed if you want to put a three-foot circular border around a tree in your yard.

C = 2r 2 · · 3

Enter: 2 x ^Shift EXP x 3 = 3’ Display: 18.85

2. How much lawn would be covered by a sprinkler with a radius of 9 feet?

A = r or · 9 9’

Enter: ^Shift EXP x 9 x = Display: 254.47

3. Find the amount of space occupied by a ball that has a diameter of 1 foot. (radius = 0.5)

V = or

x

Enter 4 a 3 x ^Shift EXP x . 5 ^Shift ► = Display 0.52