PSLE Albert had 10 more two-dollar notes than ten-dollar notes at first. He exchanged $90 worth of ten-dollar notes for two-dollar notes. How many less ten-dollar notes than two-dollar notes did Albert have after the exchange?
Number |
$2 |
$10 |
Before |
1 u + 10 |
1 u |
Change |
+ 45 |
- 9 |
After |
1 u + 10 + 45 |
1 u - 9 |
Number of ten-dollar notes that Albert exchanged into two-dollar notes
= 90 ÷ 10
= 9
Number of two-dollar notes that Albert received from the exchange
= 90 ÷ 2
= 45
Number of less ten-dollar notes than two-dollar notes
= 10 + 45 + 9
= 64
Answer: 64