6th Grade Math Textbook, Progress

Look at the diagram.

To find the amount of fencing needed to go around

the garden, will you need to know the area or

the perimeter? Perimeter

Write the formula for perimeter of a rectangle.

P
 2 
 2 wor P
2(
w)

Do you need fencing around the foursides

of the garden? No. One of the lengths is the house,

so rewrite the formula using 1 length and 2 widths.

P

 2 w

Is your answer reasonable?

The amount of fencing should be 10 m less than

the perimeter of a 10 m by 4 m rectangle.

Visualize yourself in the problem as you reread

it. List the facts and the question.

Remember, one side is the house and

the other three sides are fencing.

Facts: 10 m length

4 m width

Question:How much fencing is needed?

Larry wants to fence in a rectangular garden that

is 10 m by 4 m. If he uses 10 m of his house as

one side, how much fencing does he need to buy

for the other three sides?

Problem-Solving Strategy:

Use Drawings/Formulas

13-20

P
10 m  2 4 m

P
10 m 8 m

P
18 m

Larry will need 18 m of fencing.

10 m

4 m

4 m

Remember: One side of the house

serves as the other length.

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