Christopher and Jonathan were having bets

Christopher and Jonathan were having bets. They decide that a coin will be flipped twenty times and each time it turns heads, Christopher will give $2 to Jonathan and each time it turns out to be Tails, Jonathan will give 3$ to Christopher. After flipping for twenty times none of the both won or lost any amount. How many times did the coin landed on Heads ?

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · test #172