Sofia calculated the circumference and area of a circle with a radius of 4. C=2πr
=2(3.14)4
=25.12
A=πr2
=3.14(4)2

She then said, “The value of the circumference of a circle is always half the value of its area.” Is Sofia correct? Justify your answer.

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.