Question

A cars radiator should contain a solution of 50% antifreeze. Bae has 2 gallons of 35% antifreeze. How many gallons of 100% antifreeze should he add to his solution to produce a solution of 50% antifreeze

Answer 1

X= 240
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Equation:
anti + anti = anti
0.60x + 0.20*80 = 0.50(x+80)
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Multiply thru by 100 to get:
60x + 20*80 = 50x + 50*80
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10x = 30*80
x = 3*80
x = 240