Question 505087
Let x = the required number of gallons of the 40% glycol solution. This is to be added to (24-x) gallons of the 10% glycol solution to obtain 24 gallons of 30% glycol solution. The equation to solve for x is:
0.4x+0.1(24-x) = 0.3(24)
0.4x+2.4-0.1x = 7.2 Simplify.
0.3x+2.4 = 7.2
0.3x = 4.8
x = 16 gallons and (24-x) = 8 gallons.
The mechanic will need to mix 16 gallons of the 40% glycol solution with 8 gallons of the 10% glycol solution to obtain 24 gallons of 30% glycol solution.