The average of 17 numbers is 59

The average of 17 numbers is 59. Average of the first 9 of them is 56 and that of the last 9 is 63. Find the 9th number?

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 #87203