Ngoc needs to mix a 10% alcohol solution with a 60% alcohol solution to create 200 milliliters of a 22.5% solution. How many milliliters of each solution must Ngoc use?
Let
x -----> milliliters of solution at 10%
y -----> milliliters of solution at 60%
we have
x+y=200 ------> equation A
Remember that
10%=0.10
60%=0.60
22.5%=0.225
so
0.10x+0.60y=0.225(200) -----> equation B
solve the system of equation s A and B
Solve by graphing
using a graphing tool
see the attached figure
please wait a minute to draw the system
the solution is the point (150,50)
therefore
milliliters of solution at 10% is 150
milliliters of solution at 60% is 50