PSLE
Three men, Jed, Abe and Ken had the same number of notes. Abe and Jed each had of mix of $20-notes and $10-notes. Abe had 8 $10-notes while Jed had 21 $10-notes. Ken had only $20-notes.

1. Of the three men, who had the least money? 
2. What was the difference in the total value of Abe and Jed's notes? 
3. Jed used all his $20-notes to buy a souvenir. Ken then had $390 more than Jed. How many $20-notes did Ken have?

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

Jed had more $10-notes than Abe while Ken had only the $20-notes.  

Since Jed had the most number of $10-notes, he had the least money.

(b)
Difference in the number of notes of different values
= 21 - 8
= 13

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

Difference in the total value of Abe's and Jed's notes
= 13 x 10
= $130

(c)
Value of $10-notes that Jed had left
= 21 x 10
= $210

Total value that Ken had
= 390 + 210
= $600

Number of $20-notes that Ken had
= 600 ÷ 20
= 30

Answer(s): (a) Jed; (b) $130; (c) 30