Money Needed

A student had spent all his money, so he called his mother from college and asked if she could send him some.

"Of course, I'll send you some money, dear," Mom said.

"By the way, you left your calculus book here when you visited last month. Would you like me to send that to you too?"

"oh yeah, OK Mom," the boy replied.

So, Mom wrapped the book, together with the checks, kissed Dad goodbye and went to the post office to mail the parcel.

When she returned, Dad asked, "So, how much did you send him this time?"

"I wrote two checks, one for $20, and the other for $1000," Mom replied.

"Have you lost your mind?" Dad exclaimed.

"That's $1020!"

"Not to worry," Mom said calmly, as she kissed the top of Dad's head.

"I taped the $20 check to the cover of his book, but I put the $1000 check somewhere between the pages in Chapter 19!"