Penelope had an equal number of $100 and $1 notes. After spending 47 pieces of $1 and 12 pieces of $100 notes, the ratio of the $100 notes to $1 notes left was 8 : 3. Find the value of the notes left.
| |
$100 |
$1 |
| Before |
8 u + 12 |
3 u + 47 |
| Change |
- 12 |
- 47 |
| After |
8 u |
3 u |
Number of $100 notes at first = 8 u + 12
Number of $1 notes at first = 3 u + 47
The number of $100 and $1 notes at first is the same.
8 u + 12 = 3 u + 47
8 u - 3 u = 47 - 12
5 u = 35
1 u = 35 ÷ 5 = 7
Value of $100-notes left
= 8 u x 100
= 8 x 7 x 100
= $5600
Value of $1-notes left
= 3 u x 1
= 3 x 7 x 1
= $21
Value of notes left
= 5600 + 21
= $5621
Answer(s): $5621
