Question

the sides of a rectangle are the ratio 2:5. (for every 2cm of the width, the length is 5cm) the perimeter of the rectangle is 70cm. what is the with of thr rectangle?

Answer 1

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Ratio
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Width : Length
    2    :   5 

Let x be the scale factor

Width : Length
    2x    :   5x

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Form equation and solve x
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Perimeter = 2(Length + Width)
70 = 2(5x + 2x)
70 = 2(7x)
70 = 14x
14x = 70
x = 5

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Find Length and Width
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Length = 5x 
Length = 5(5) 
Length = 25

Width = 2x
Width = 2(5)
Width = 10

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Answer: Length = 25 cm, Width = 10 cm
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