mike's automall has 130 cars on clearance all either red blue or green. there are four times as many red as green, and twice as many blue as red. how many of each color do they have
Solve this set of equations:
R + B + G = 130
R = 4 G
B = 2 R
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Here's a way to proceed:
B = 8 G
4 G + 8 G + G = 130
13 G = 130
G = 10
Take it from there