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Step-2

Title: Area of semicircle

Grade: 7-a Lesson: S1-L4

Explanation:

Step	Type	Explanation	Answer
1	Formula:	Area of a semicircle.	A = \$\frac{\pi r^2}{2}\$
2	Step	Substitute \$22/7\$ for \$pi\$ and 14 for r	A = \$\frac{\frac{22}{7} (14)^2}{2}\$
3	Step	Cancel out common factor.	A = \$\frac{\frac{22}{\cancel{7}^1} \times \cancel{14}^2 \times 14}{2}\$
4	Step	Multiply.	A = \$\frac{\frac{22}{1} \times 2 \times 14}{2}\$ A = \$\frac{22 \times 2 \times 14}{2}\$
5	Step	Divide.	A = \$\frac{616}{2}\$ A = \$\frac{\cancel616^308}{\cancel{2}^1}\$
6	Step	Answer.	A = 308
7		The area is	\$308 m^2\$

Step

Type

Explanation

Answer

Formula:

Area of a semicircle.

A = \$\frac{\pi r^2}{2}\$

Step

Substitute \$22/7\$ for \$pi\$ and 14 for r

A = \$\frac{\frac{22}{7} (14)^2}{2}\$

Step

Cancel out common factor.

A = \$\frac{\frac{22}{\cancel{7}^1} \times \cancel{14}^2 \times 14}{2}\$

Step

Multiply.

A = \$\frac{\frac{22}{1} \times 2 \times 14}{2}\$
A = \$\frac{22 \times 2 \times 14}{2}\$

Step

Divide.

A = \$\frac{616}{2}\$
A = \$\frac{\cancel616^308}{\cancel{2}^1}\$

Step

Answer.

A = 308

The area is

\$308 m^2\$