Question

1. Which of the equations below could be used to find the radius of a dinner plate whose area is 255 square inches?

255 =
`\pi r^(2)`r2
255 =
`image`
255 = 2
`\pi` r


2. Which of the following is the best approximation of the area of a circle whose diameter is 14 feet?

44 square feet
88 square feet
154 square feet
616 square feet



3. The spray from a sprinkler creates a circle with a radius of 15 feet. Which of the following is the best approximation of how many square feet of grass the sprinkler covers?

47
94
225
707

Answer 1

1.
S=πr² ⇒ 255=πr²

2.
d=14 feet
r=d/2 = 14/2 = 7 feet
S = πr² = 3.14 * 7² = 3.14 * 49 ≈ 154 square feet

3.
S = πr² = 3.14 * 15² = 3.14 * 225 ≈ 707 square feet.

Answer 2

I'm not 100% sure but I think #2 is B and #3 is D but if im wrong Im so sorry