PSLE Eric had 20 more one-dollar notes than ten-dollar notes at first. He exchanged $70 worth of ten-dollar notes for one-dollar notes. How many less ten-dollar notes than one-dollar notes did Eric have after the exchange?
Number |
$1 |
$10 |
Before |
1 u + 20 |
1 u |
Change |
+ 70 |
- 7 |
After |
1 u + 20 + 70 |
1 u - 7 |
Number of ten-dollar notes that Eric exchanged into one-dollar notes
= 70 ÷ 10
= 7
Number of one-dollar notes that Eric received from the exchange
= 70 ÷ 1
= 70
Number of less ten-dollar notes than one-dollar notes
= 20 + 70 + 7
= 97
Answer: 97