A man has some hens and cows

A man has some hens and cows. If the number of heads be 48 and the number of feet equals 140, then the number of hens will be:

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 #835