How many gallons of a 70​% antifreeze solution must be mixed with 100 gallons of 15​% antifreeze to get a mixture that is 60​% ​antifreeze? Use the​ six-step method.

Answer 1

X is the amount of 70% antifreeze

70% = 0.7

15% = 0.15

60% = 0.6

the amount of anti-freeze is:

0.7x + 100 * 0.15 = (x+100) * 0.6

0.7x + 15 = 0.6x + 60

0.1x + 15 = 60

0.1x = 45

x = 450