Henry Ernest Dudeney/Puzzles and Curious Problems/130 - Milk and Cream/Solution

by : $130$

 * Milk and Cream

Solution
Half a pint.

Proof
Let $v_c$ be the volume of cream in a volume $v$ of whole milk.

Let $w$ be the quantity of skimmed milk needed to reduce the volume of cream to $4 \%$.

We have:

As we are told that $v$ is $1$ quart, it follows that the amount of skimmed milk to be added is half a pint.