Opal had an equal number of $20 and $50 notes. After spending 50 pieces of $50 and 47 pieces of $20 notes, the ratio of the $20 notes to $50 notes left was 4 : 1. Find the value of the notes left.
| |
$20 |
$50 |
| Before |
4 u + 47 |
1 u + 50 |
| Change |
- 47 |
- 50 |
| After |
4 u |
1 u |
Number of $20 notes at first = 4 u + 47
Number of $50 notes at first = 1 u + 50
The number of $20 and $50 notes at first is the same.
4 u + 47 = 1 u + 50
4 u - 1 u = 50 - 47
3 u = 3
1 u = 3 ÷ 3 = 1
Value of $20-notes left
= 4 u x 20
= 4 x 1 x 20
= $80
Value of $50-notes left
= 1 u x 50
= 1 x 1 x 50
= $50
Value of notes left
= 80 + 50
= $130
Answer(s): $130
