Question 224305
100% * 30 + 20% * 50 = (x%) * (30+50)
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1*30 +.2*50 = x* 80
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30+10= 80x
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40=80x
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.5 = x,,,,,,,or  50%
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check,,,,30 + 10 = .5*80=40,,,,,ok
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