Marissa, Keith and Tony all go to Disneyland many times each summer

Marissa, Keith and Tony all go to Disneyland many times each summer. Together, they have all gone a total of 65 times. Marissa and Keith have gone 55 times total, while Keith and Tony have gone 40 times total. How many times has Keith gone just by himself?

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #973