Question 181287
The problem states,Solve for the unknown (X) in the following proportions: 
1) 2/10 = 16/x
The easiest way is to "cross multiply."  Multiply the NUM of one by the DEN of the other.
2x = 160
 x = 80
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2) 7/30 = x/90 
30x = 630
x = 21
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