20 quarts of peanut oil worth 19 cents per quart must be mixed.
<u><em>Explanation</em></u>
Lets assume, x quarts of peanut oil worth 19 cents per quart must be mixed.
Now we are mixing 100 quarts of another peanut oil worth 25 cents per quart with that x quarts. So, the total amount of the mixture
quarts, which will worth 24 cents per quart.
Total price of x quarts oil
cents
Total price of 100 quarts oil
cents
and total price of the mixture
cents
So the equation will be :

So, 20 quarts of peanut oil worth 19 cents per quart must be mixed.