Nat, Joe and Ben had the same number of notes. Nat and Joe had a mix of $20-notes and $10-notes. Joe had 7 $20-notes while Nat had 15 $20-notes. Ben only had $20-notes.

1. Who had the least amount of money?
2. How much less did Joe have than Nat?
3. Nat used all his $10-notes to buy a wallet. He then had $480 less than Ben. How many $20-notes did Ben have?

(a)
The three boys had the same number of notes.
$20-notes have a higher denomination than $10-notes.

Since Joe had the least number of $20-notes, he had the least money.

(b)
Number of less $20-notes that Joe had than Nat
= 15 - 7
= 8

Difference in the value of $20-note and $10-note
= 20 - 10
= $10

Amount that Joe had less than Nat
= 8 x 10
= $80

(c)
Value of $20-notes that Nat had left
= 15 x 20
= $300

Total value that Ben had
= 300 + 480
= $780

Number of $20-notes that Ben had
= 780 ÷ 20
= 39

Answer(s): (a) Joe; (b) $80; (c) 39