Boy shepherd B with his one sheep behind him asked shepherd A "Are there 100 sheep in your flock?".
Shepherd A replies "Yet add the same flock, the same flock again, half, one quarter flock and your sheep. There are then 100 sheep altogether."
How many sheep is in shepherd A's flock?
Source: Problem in Cheng Dawei's Suanfa tong zong, 1592