The ratio of the number of $5-notes to $10-notes in Kylie's jar was 1 : 4. Kylie exchanged 14 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 Kylie's jar at first?
|
$5-notes |
$10-notes |
Before |
1 u |
4 u |
Change |
+ 28 |
- 14 |
After |
1 u + 28 |
4 u - 14 |
Value of 14 pieces of $10-notes
= 14 x 10
= $140
Number of $5-notes that Kylie exchanged for
= 140 ÷ 5
= 28
After the exchange, Kylie had an equal number of $5-notes and $10-notes.
4 u - 14 = 1 u + 28
4 u - 1 u = 28 + 14
3 u = 42
1 u = 42 ÷ 3 = 14
Number of $5-notes at first
= 1 u
= 14
Value of $5-notes at first
= 14 x 5
= $70
Number of $10-notes at first
= 4 u
= 4 x 14
= 56
Value of $10-notes at first
= 56 x 10
= $560
Total value of $5-notes and $10-notes at first
= 70 + 560
= $630
Answer(s): $630