Suppose 8 pints of a 19% alcohol solution is mixed with 2 pints of an 80% alcohol solution. What is the concentration of alcohol in the new 10 pint mixture

Question

Looking to see how to solve the solution concentration problem

Answer 1

We can find the amount of alcohol in the 10 pint mixture by adding the total alcohol in the two smaller solutions.

 

If the first solution is 19% alcohol, that means that 19% of the 8 pints should be alcohol. This is found by multiplying 8*.19 to get 1.52 pints.

 

In the second solution, 80% of the 2 pints is alcohol, which is 2*.80 = 1.6 pints.

 

When we mix the two solutions, the amount of alcohol is added together. 1.52 + 1.6 = 3.12 pints of alcohol in the 10 pint mixture.

 

The new concentration would be 3.12/10 = .312 or 31.2%

Answer 2

8(19%) + 2(80%) = (8 + 2)x = 10x

 

Solve for x.

 

x = [8(19) + 2(80)]/10 % = 31.2%