Answers

2015-09-18T14:49:58+08:00
"How many balls are there in the box"
let this be the x.

"There are 5 less than twice as many as blue"
2y - 5

So, 
12(2) - 5
24 - 5
19

So the conclusion is:
There are 19 blue balls, and 12 red balls in the box. There are 31 (19 + 12) balls overall in the box, and blue balls (19) are more than red balls (12) in the box by 7 balls (19 - 12) 
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