Question

Lesson 4: Proportional Relationships a 2. A recip Equations the qu a. Let's write equations describing proportional relationships. b. 4.1: Number Talk: Division Find each quotient mentally. C. 645 - 100 645:50 48.6 - 30 48.6 + x

Answer 1

`(645)/(100)=6.45`

Move the decimal point of 645 two units left ( You are dividing by 100)

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`(645)/(50)=(129)/(10)=12.9`

Simplify 645/50 as 129/10, now move the decimal point of 129 one unit left (You are dividing by 10).

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`(48.6)/(30)=(243)/((5)/(30))=(243)/(150)=(81)/(50)`

Express 48.6 as 243/5, then use division of fractions to get 243/150, then simplify 243/150 as 81/50

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`(48.6)/(x)=((243)/(5))/(x)=(243)/(5x)`

Express 48.6 as 243/5, then use division of fractions to get 243/5x