Mother-in-law

Standing at the edge of the lake, a man saw a woman flailing about in the deep water. Unable to swim, the man screamed for help. Banta ran up.

The man said, "My wife is drowning and I can't swim. Please save her. I'll give you Rs 500."

Banta dove into the water. In ten powerful strokes, he reached the woman, put his arm around her, and swam back to shore.

Depositing her at the feet of the man, Banta said, "Okay, where's my Five hundred?"

The man said, "Look, when I saw her going down for the third time, I thought it was my wife. But this is my mother-in-law." Banta reached into his pocket and said, "Just my luck. How much do I owe you?"