Problema Solution
pure acid is to be added to a 10% acid solution to obtain 90L of 85% solution. what amounts of each should be used?
Answer provided by our tutors
let
x = the liters of 10% acid solution
y = the liters of pure acid that is 100% acid solution
10% of x + 100% of y = 85% of 90 liters
thus we have the system of equations
x + y = 90
0.10*x + 1.00*y = 0.85*90
by solving the system we find
x = 15 liters
y = 7 liters
we need 15 liters of 10% acid solution and 7 liters of pure acid.