PSLE Simon had 12 more ten-dollar notes than fifty-dollar notes at first. He exchanged $900 worth of fifty-dollar notes for ten-dollar notes. How many less fifty-dollar notes than ten-dollar notes did Simon have after the exchange?
Number |
$10 |
$50 |
Before |
1 u + 12 |
1 u |
Change |
+ 90 |
- 18 |
After |
1 u + 12 + 90 |
1 u - 18 |
Number of fifty-dollar notes that Simon exchanged into ten-dollar notes
= 900 ÷ 50
= 18
Number of ten-dollar notes that Simon received from the exchange
= 900 ÷ 10
= 90
Number of less fifty-dollar notes than ten-dollar notes
= 12 + 90 + 18
= 120
Answer: 120