Nora had an equal number of $10 and $100 notes. After spending 16 pieces of $100 and 13 pieces of $10 notes, the ratio of the $10 notes to $100 notes left was 8 : 5. Find the value of the notes left.
| |
$10 |
$100 |
| Before |
8 u + 13 |
5 u + 16 |
| Change |
- 13 |
- 16 |
| After |
8 u |
5 u |
Number of $10 notes at first = 8 u + 13
Number of $100 notes at first = 5 u + 16
The number of $10 and $100 notes at first is the same.
8 u + 13 = 5 u + 16
8 u - 5 u = 16 - 13
3 u = 3
1 u = 3 ÷ 3 = 1
Value of $10-notes left
= 8 u x 10
= 8 x 1 x 10
= $80
Value of $100-notes left
= 5 u x 100
= 5 x 1 x 100
= $500
Value of notes left
= 80 + 500
= $580
Answer(s): $580
