Question 993419

How much 60% antifreeze solution and 30% antifreeze solution should be combined to give 55 gallons of 42% antifreeze solution? Thank you!
<pre>Let the amount of 60% solution to mix, be S
Then the amount of 30% solution to be mixed = 55 - S
The following antifreeze-solution equation is thus formed:
.6S + .3(55 - S) = .42(55)
.6S + 16.5 - .3S = 23.1
.6S - .3S = 23.1 - 16.5
.3S = 6.6
S, or amount of 60% solution to mix = {{{6.6/.3}}}, or {{{highlight_green(22)}}} gallons
Amount of 30% solution to be mixed = 55 - 22, or {{{highlight_green(33)}}} gallons