In a class, the average age of 40 boys is 18 years…

In a class, the average age of 40 boys is 18 years and the average of 30 girls is 15 years. what is the average age of the whole class?

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 #33932