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Glencoe Math: Course 3, Volume 2

GM

Glencoe Math: Course 3, Volume 2 View details

1. Volume of Cylinders

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Exercise 21 Page 596

Recall the formula for finding the area of a circle.

About $201.1 cm^{2}$

Practice makes perfect

We are given a circle and we want to find its area.

The area of a circle with radius

r

is calculated using the formula below.

A = π r^{2}

From the figure we know that the radius of the circle is

8 cm .

By substituting

8

for

r

in the formula, we can calculate

A .

A = π r^{2}

$r = 8$

A = π (8)^{2}

Calculate power

A = π (64)

Use a calculator

A = 201.061930 \dots

Round to $1$ decimal place(s)

A \approx 201.1

The area of the circle is approximately

201.1

square centimeters.

Subchapter links

Guided Practice p.592

Independent Practice p.593-594

H.O.T. Problems p.594

Standardized Test Practice p.594-596

Extra Practice p.595

Common Core Review p.596