Nora had an equal number of $20 and $50 notes. After spending 15 pieces of $50 and 11 pieces of $20 notes, the ratio of the $20 notes to $50 notes left was 5 : 1. Find the value of the notes left.
| |
$20 |
$50 |
| Before |
5 u + 11 |
1 u + 15 |
| Change |
- 11 |
- 15 |
| After |
5 u |
1 u |
Number of $20 notes at first = 5 u + 11
Number of $50 notes at first = 1 u + 15
The number of $20 and $50 notes at first is the same.
5 u + 11 = 1 u + 15
5 u - 1 u = 15 - 11
4 u = 4
1 u = 4 ÷ 4 = 1
Value of $20-notes left
= 5 u x 20
= 5 x 1 x 20
= $100
Value of $50-notes left
= 1 u x 50
= 1 x 1 x 50
= $50
Value of notes left
= 100 + 50
= $150
Answer(s): $150
