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Problem 501

Algebra Difficulty 2.3 Multiple choice CEMC Fermat · Canada · 2023

Three tanks contain water. The number of litres in each is shown
in the table below:

Tank A	Tank B	Tank C
3600 L	1600 L	3800 L

Water is moved from each of Tank A and Tank C into Tank B so that
each tank contains the same volume of water. How many litres of water
are moved from Tank A to Tank B?

Pick one

Official solution

In total, the three tanks contain $3600\text{ L} + 1600\text{ L} + 3800\text{ L} = 9000\text{ L}$ .

If the water is divided equally between the three tanks, each will
contain $\frac{1}{3} \cdot 9000\text{ L} = 3000\text{ L}$ .

Therefore, $3600\text{ L} - 3000\text{ L} = 600\text{ L}$ needs to be moved from Tank A to Tank B.

(We note that 800 L would also need to be moved from Tank C to Tank B,
and at this point, the three tanks will contain 3000 L.)

Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty, ordering) added by this project.