A radiator holds 8 liters Suppose you have a bottle of pure

. A radiator holds 8 liters. Suppose you have a bottle of pure antifreeze and a bottle of 10% antifreeze mixture. How much of each must you need to make enough of a 77.5% mixture to fill the radiator?

How liters of pure antifreeze?

How many liters of 10% antifreeze?

Solution

Let, x liters of pure antifreeze and y of mixture

So, x+y=8

(x+0.1y)/(x+y)=77.5/100

100x+10y=77.5x+77.5y

22.5x=67.5y

x=3y

x+y=8

4y=8

y=2

So, 2 literes of 10% antifreeze and 6 litres of pure antifreeze