Olivia had an equal number of $2 and $10 notes. After spending 49 pieces of $10 and 13 pieces of $2 notes, the ratio of the $2 notes to $10 notes left was 7 : 3. Find the value of the notes left.
| |
$2 |
$10 |
| Before |
7 u + 13 |
3 u + 49 |
| Change |
- 13 |
- 49 |
| After |
7 u |
3 u |
Number of $2 notes at first = 7 u + 13
Number of $10 notes at first = 3 u + 49
The number of $2 and $10 notes at first is the same.
7 u + 13 = 3 u + 49
7 u - 3 u = 49 - 13
4 u = 36
1 u = 36 ÷ 4 = 9
Value of $2-notes left
= 7 u x 2
= 7 x 9 x 2
= $126
Value of $10-notes left
= 3 u x 10
= 3 x 9 x 10
= $270
Value of notes left
= 126 + 270
= $396
Answer(s): $396
