Proportional Reasoning Review: Scales and rates.

Posted on May 15, 2017 by jamesw2016

General conceopts:

a/b=x/y

a/b is the scale factor.

x/a is the image

y/b is the actual picture.

to find B: (y/x)*a=b ex: 1/b= 6/18 18/6=3 3/1=3 b=3

to find x: a*(y/b)=x ex: 1/3=x/18 18/3=6 6*1=6 x=6

to find y: b*(x/a)=y ex: 1/3=6/y 6/1=6 6*3=18 y=18

Rational Numbers Review

{[( $\frac{4}{6} \times {3})^2$ +( $\sqrt {144}) \div {2}$ ]x2}

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{[( $\frac{12}{6})^2+(12) \div{2}$ ]x2}

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{[(2) $^2+(12) \div 2$ ]x2}

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{[(4)+(12) $\div 2$ ]x2}

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{[(4)+(6)]x2}

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{[10]x2}

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{20}

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