D = diameter
A = area
Pi = 3.14
R = radius
First, we have to find the area of the garden.
To find A we have to divide D by 2, which will result in the radius.
17.5 / 2 = 8.75
Then we multiply R to the second power by multiplying it by itself.
8.75 x 8.75 = 76.5625
Then multiply 76.5625 by Pi.
76.5625 x 3.14 = 240.40625
The divide 240.40625 by 30.
240.40625 x 30 = 8.014
Lisa will need about 8.014 teaspoons of fertilizer to cover her garden.
I hope this helps! :)
