How many quarts of pure antifreeze must be added to 2 quarts of a 50​% antifreeze solution to obtain a ​60% antifreeze​ solution?

Question

How many quarts of pure antifreeze must be added to 2 quarts of a 50​% antifreeze solution to obtain a ​60% antifreeze​ solution?

Answer 1

x + 2(.5) =x+1 = .6(x+2)= .6x+1.2

.4x = .2

x = .2/.4 = 1/2 quart of pure antifreeze

mixed with 2 quarts 50% to get 2.5 quarts of 60%

60-50=10

100-60=40

40/10= 4 times as much 50% as 100%

2 = 4 times 1/2