Area of partial circles

Front

What is the formula for the area of a circle?

Back

The area of a circle is given by the formula A = πr², where r is the radius of the circle.

Front

How do you calculate the area of a semicircle?

Back

The area of a semicircle is half the area of a full circle, so it is A = (1/2)πr².

Front

What is the area of a quarter circle?

Back

The area of a quarter circle is one-fourth the area of a full circle, so it is A = (1/4)πr².

Front

How do you find the area of a three-quarter circle?

Back

The area of a three-quarter circle is three times the area of a quarter circle, so it is A = (3/4)πr².

Front

What is the value of π (pi) to two decimal places?

Back

π (pi) is approximately 3.14.

Front

If the radius of a circle is 7, what is the area of the semicircle?

Back

The area of the semicircle is A = (1/2)π(7)² = 76.96 (rounded to two decimal places).

Front

What is the area of a circle with a radius of 10?

Back

The area of the circle is A = π(10)² = 314.16.

Front

How do you round a number to the nearest hundredth?

Back

To round to the nearest hundredth, look at the third decimal place. If it is 5 or more, round up the second decimal place by one.

Front

What is the area of a three-quarter circle with a radius of 8?

Back

The area of the three-quarter circle is A = (3/4)π(8)² = 150.80 (rounded to two decimal places).

Front

What is the area of a quarter circle with a radius of 5?

Back

The area of the quarter circle is A = (1/4)π(5)² = 19.63 (rounded to two decimal places).