Problema Solution
Mr. Smith needs 2 Liters of a 65% acid solution. He has a 40% solution and an 80% solution on hand with which to make the mixture. How much of each should he use?---Setup a system of algebraic equations and solve
Answer provided by our tutors
let 'x' represent the amount of 40% solution used, then '2-x' represents the amount of 80% solution used
0.65(2) = 0.4x + 0.8(2-x)
solving for 'x' we have x=0.75
2 - 0.75 = 1.25
0.75 liters of 40% solution should be mixed with 1.25 liters of 80% solution
now, to solve this using a system of equations, we would let 'a' represent the amount of 40% solution used and 'b' represent the amount of 80% solution used, then we would have these two equations:
a+b=2
0.65(2) = 0.4a + 0.8b
..solving this system would produce the same answer as above, it's just a bit harder