A large dining room table is in the shape of a semicircle with a diameter of 12 feet. What is the area of the table? (Use pi = 3.14)?

1 Answer
Jun 15, 2017

A=18pi ft^2 = 56.549 ft^2

Explanation:

Given:
shape = semicircle [half of a circle]
d = 12 ft
Area = ?

Formulas:
Area of Circle= pir^2
d=2r [Remember radius is half the length of the diameter!]
pi=3.14

Since a semicircle is HALF of a circle, multiply the area of the circle by (1/2) to get the area of a semicircle:
Area of Circle= pir^2 -> Area of Semicircle=(1/2)pir^2

The formula needs the RADIUS, not the DIAMETER. Divide diameter by 2 to get radius.
d=2r
12=2r
r=6

Substitute values for variables in the formula for *area of a semicircle.*
A=(1/2)pir^2
A=(1/2)pi(6)^2
A=(1/2)pi(36)
A=18pi = 56.549

The area of the dining room table is 18pi ft^2 or 56.549 ft^2.