Hello, lilikoipssn!

I have milk that contains 1% fat and milk that contains 4% fat.

A customer wants a double latte made with 1/3 a pint of 2% milk.

How much of each type of milk should I use ?

Let = amount of 1% milk.

. . It contains: . pints of fat.

Then = amount of 4% milk.

. . It contains: . pints of fat.

Hence, the mixture contains a total of: . pints of fat.

But we know that the mixture will be pints which is 2% fat.

. . It contains: . pints of fat.

We just described the final amount of fat intwoways.

. . There is our equation . . .