The sum of how many terms of the series 6 + 12…

The sum of how many terms of the series 6 + 12 + 18 + 24 + ... is 1800 ?

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 #8967