Health insurance Plan P requires the insured person to pay …500

Health insurance Plan P requires the insured person to pay $500 but then the insurance pays 70% of the cost over $500. Plan Q requires the insured to pay the initial $400, but then pays 60% of the cost over $400. Which of the following is a cost level for which both insurance plans pay out the same amount?

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 #19316