Question 1135500

Your 10 gallons of 40% grape juice is too sweet. How many gallons of 10% grape juice should be added to make 30% grape juice?
<pre>Let amount of 10% juice to be added, be T
Then we get: .1T + .4(10) = .3(T + 10)
.1T + 4 = .3T + 3
.1T - .3T = 3 - 4
- .2T = - 1
Amount of 10% juice to add, or {{{highlight_green(matrix(1,6, T, "=", (- 1)/(- .2), "=", 5, gallons))}}}