Company X provides bottled water to its employees in 10 liter bottles…

Company X provides bottled water to its employees in 10 liter bottles, $2 each. At least how many 10L bottles must Company X buy monthly, so that new contract with $50 fixed monthly rate and $1 for 50L bottle each paid off? (Assume that no other costs apply)

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #4362