Math week day one

Monday: "Two Tens For a Five."
Bud Abbott and Lou Costello's first
scene in the movie 'One Night in the
Tropics' is a classic.
Abbott cons Costello by simply asking
for change. "Have you got 2 tens for a
five?" he asks. As Lou realised he has
been duped, Bud snaps back: "OK, here's
your five, give me back my 2 tens!" The
skit carries on and Lou loses money!
"Two Tens for a Five" is a classic vaudeville
routine made famous by Bud Abbott and Lou
Costello and has been repeated many times
over the years.

Abbott: Have you got two tens for a five?
Costello: Just so happen to have it.
Lou gives Bud ten dollars and Bud gives Lou five
dollars.
Costello: Just a minute, just one minute!
Abbott: Something wrong?
Costello: Fifteen dollars just went south!
Abbott: What do you mean?
Costello: You gave me a lot of your fast talk, you said 'do you have
two tens for a five' and I gave you two tens for a five.
Abbott: Just a minute, are you accusing me of cheating?
Costello: No, but you got two tens for a five.
Abbott: Alright here's your five now gimme back my two tens.
Costello: Okay, that's better.
Bud gives Lou five dollars and Lou gives Bud ten dollars.
After a slight pause Lou realises he has been conned again.
Costello: What are you doing?
Abbott: What’s wrong now?Costello: Look Abbott, here's two tens gimme a five!
Abbott: Certainly.
Lou gives Bud ten dollars and Bud gives Lou five dollars.
Costello: HA HA HA HAAA!
You did it to me...
You did it to me again.
Abbott: Oh come on.

The 300 Dollar Question. 

How much did Lou lose? : 40 x