2021 JMC 10 Problems/Problem 5
Problem
A mixture has grams of aluminum and
grams of barium. Nir the chemist uses magic to remove some aluminum. Now, exactly
of the mixture consists of aluminum. How many grams of the mixture now remain?
Solution
Let be the amount of aluminum removed, in grams. There are
grams of aluminum left and
grams of the mixture left. So,
The mixture has
grams.