PSLE
Three boys, Rio, Kai and Ace had the same number of notes. Rio and Kai each had of mix of $10-notes and $2-notes. Rio had 5 $2-notes while Kai had 10 $2-notes. Ace had only $10-notes.

1. Of the three boys, who had the most money? 
2. What was the difference in the total value of Rio and Kai's notes? 
3. Kai used all his $10-notes to buy a souvenir. He then had $280 less than Ace. How many $10-notes did Ace have?

(a)
The three boys had the same number of notes.
$2-notes have a lower denomination than $10-notes.

Since Ace had only $10-notes, he had the most money.

(b)
Difference in the number of notes of different values
= 10 - 5
= 5

Difference in the value of $10-notes and $2-notes
= 10 - 2
= $8

Difference in the total value of Rio's and Kai's notes
= 5 x 8
= $40

(c)
Value of $2-notes that Kai had left
= 10 x 2
= $20

Total value that Ace had
= 280 + 20
= $300

Number of $10-notes that Ace had
= 300 ÷ 10
= 30

Answer(s): (a) Ace; (b) $40; (c) 30