Opal had an equal number of $5 and $50 notes. After spending 20 pieces of $50 and 14 pieces of $5 notes, the ratio of the $5 notes to $50 notes left was 7 : 4. Find the value of the notes left.
| |
$5 |
$50 |
| Before |
7 u + 14 |
4 u + 20 |
| Change |
- 14 |
- 20 |
| After |
7 u |
4 u |
Number of $5 notes at first = 7 u + 14
Number of $50 notes at first = 4 u + 20
The number of $5 and $50 notes at first is the same.
7 u + 14 = 4 u + 20
7 u - 4 u = 20 - 14
3 u = 6
1 u = 6 ÷ 3 = 2
Value of $5-notes left
= 7 u x 5
= 7 x 2 x 5
= $70
Value of $50-notes left
= 4 u x 50
= 4 x 2 x 50
= $400
Value of notes left
= 70 + 400
= $470
Answer(s): $470
