Ivory had an equal number of $5 and $1 notes. After spending 39 pieces of $1 and 15 pieces of $5 notes, the ratio of the $5 notes to $1 notes left was 7 : 1. Find the value of the notes left.
| |
$5 |
$1 |
| Before |
7 u + 15 |
1 u + 39 |
| Change |
- 15 |
- 39 |
| After |
7 u |
1 u |
Number of $5 notes at first = 7 u + 15
Number of $1 notes at first = 1 u + 39
The number of $5 and $1 notes at first is the same.
7 u + 15 = 1 u + 39
7 u - 1 u = 39 - 15
6 u = 24
1 u = 24 ÷ 6 = 4
Value of $5-notes left
= 7 u x 5
= 7 x 4 x 5
= $140
Value of $1-notes left
= 1 u x 1
= 1 x 4 x 1
= $4
Value of notes left
= 140 + 4
= $144
Answer(s): $144
