The ratio of the number of $5-notes to $10-notes in Elyse's bag was 1 : 6. Elyse exchanged 15 pieces of $10-notes for $5-notes. She then had an equal number of $5-notes and $10-notes. What was the total value of $5-notes and $10-notes in Elyse's bag at first?
| |
$5-notes |
$10-notes |
| Before |
1 u |
6 u |
| Change |
+ 30 |
- 15 |
| After |
1 u + 30 |
6 u - 15 |
Value of 15 pieces of $10-notes
= 15 x 10
= $150
Number of $5-notes that Elyse exchanged for
= 150 ÷ 5
= 30
After the exchange, Elyse had an equal number of $5-notes and $10-notes.
6 u - 15 = 1 u + 30
6 u - 1 u = 30 + 15
5 u = 45
1 u = 45 ÷ 5 = 9
Number of $5-notes at first
= 1 u
= 9
Value of $5-notes at first
= 9 x 5
= $45
Number of $10-notes at first
= 6 u
= 6 x 9
= 54
Value of $10-notes at first
= 54 x 10
= $540
Total value of $5-notes and $10-notes at first
= 45 + 540
= $585
Answer(s): $585
