A (brand new) riddle, Merle was checking out at the grocery store. Ethel, a friendly cashier, said the total was $63.59. He gave her a $100 bill and she began laughing as she counted out his change. See comments...

Full riddle,

Merle was checking out at the grocery store. Ethel, a friendly cashier, said the total was $63.59. He gave her a $100 bill and she began laughing as she counted out his change. Then she gave him a high five and Merle left the store chuckling.

What was so funny?

His change consisted of

1 -$20 bill

1-$10 bill

1-$5 bill

1-$1 bill

1-quarter

1-dime

1-nickel

1 penny