A chemist working in a lab has a bottle of 40 alcohol soluti

A chemist working in a lab has a bottle of 40% alcohol solution and a bottle of 5% alcohol solution. How many liters of each does he need to mix so that he can get a mixture of 60 liters of 12% alcohol solution? (You must show correct equation set up and all work.)

Solution

Let us assume that x be solution required in litres of mixing

Given that 1 bottle with 40% and other with 5% alcohol

then

40%x+5%(60-x)=12%*60

0.4x+0.05(60-x)=0.12(60)

0.4x+3-0.05x=7.2

0.35x+3=7.2

0.35x=7.2-3

0.35x=4.2

x=4.2/0.35

x=12 liters

So 12 lts are required from each