The ratio of the number of $2-notes to $10-notes in Kylie's bag was 1 : 4. Kylie exchanged 14 pieces of $10-notes for $2-notes. She then had an equal number of $2-notes and $10-notes. What was the total value of $2-notes and $10-notes in Kylie's bag at first?
| |
$2-notes |
$10-notes |
| Before |
1 u |
4 u |
| Change |
+ 70 |
- 14 |
| After |
1 u + 70 |
4 u - 14 |
Value of 14 pieces of $10-notes
= 14 x 10
= $140
Number of $2-notes that Kylie exchanged for
= 140 ÷ 2
= 70
After the exchange, Kylie had an equal number of $2-notes and $10-notes.
4 u - 14 = 1 u + 70
4 u - 1 u = 70 + 14
3 u = 84
1 u = 84 ÷ 3 = 28
Number of $2-notes at first
= 1 u
= 28
Value of $2-notes at first
= 28 x 2
= $56
Number of $10-notes at first
= 4 u
= 4 x 28
= 112
Value of $10-notes at first
= 112 x 10
= $1120
Total value of $2-notes and $10-notes at first
= 56 + 1120
= $1176
Answer(s): $1176
