Risa had an equal number of $5 and $100 notes. After spending 47 pieces of $100 and 26 pieces of $5 notes, the ratio of the $5 notes to $100 notes left was 4 : 1. Find the value of the notes left.
| |
$5 |
$100 |
| Before |
4 u + 26 |
1 u + 47 |
| Change |
- 26 |
- 47 |
| After |
4 u |
1 u |
Number of $5 notes at first = 4 u + 26
Number of $100 notes at first = 1 u + 47
The number of $5 and $100 notes at first is the same.
4 u + 26 = 1 u + 47
4 u - 1 u = 47 - 26
3 u = 21
1 u = 21 ÷ 3 = 7
Value of $5-notes left
= 4 u x 5
= 4 x 7 x 5
= $140
Value of $100-notes left
= 1 u x 100
= 1 x 7 x 100
= $700
Value of notes left
= 140 + 700
= $840
Answer(s): $840
