Question

The perimeter of a semicircle is 15.42 yards. What is the semicircle's diameter?

Use 3.14 for ​.

Answer 1

6 yards

Explanation:

Perimeter = arc length + diameter

= ½(2pi × r) + 2r

15.42 = 3.14r + 2r

15.42 = 5.14r

r = 3

Diameter = 2r

2(3)

6

Answer 2

The perimeter of a semi circle can be found using [ 1/2 * π * d + d = 15.42 ]

d = diameter

The diameter of a semi circle can be found using [ d(π/2 + 1) = 15.42 ]

π ≈ 3.14

Now, solve for d.

d(π/2 + 1) = 15.42

~Divide π/2 + 1 to both sides

d(π/2 + 1) ÷ π/2 + 1 = 15.42 ÷ π/2 + 1

~Simplify

d = 30.84/π + 2

~Substitute π with 3.14

d = 30.84/3.14 + 2

~Add

d = 30.84/5.14

~Divide

d = 6

Therefore, the diameter of the semicircle is 6 yards.

Best of Luck!