Measurement Volume

Question

It was discovered nine days later that one of the 500 ml containers had been leaking at a rate of 20 ml a day. How much oil would be left in that container?

Answer 1

If the 500 ml container had been full at the beginning, and if the leakage rate was constant for 9 days, then 9 days after the leak the total leakage would have been 20*9 or 180 ml loss. Therefore 500 - 180 ml (320 ml) remains.