Usha had an equal number of $10 and $20 notes. After spending 34 pieces of $20 and 25 pieces of $10 notes, the ratio of the $10 notes to $20 notes left was 5 : 2. Find the value of the notes left.
| |
$10 |
$20 |
| Before |
5 u + 25 |
2 u + 34 |
| Change |
- 25 |
- 34 |
| After |
5 u |
2 u |
Number of $10 notes at first = 5 u + 25
Number of $20 notes at first = 2 u + 34
The number of $10 and $20 notes at first is the same.
5 u + 25 = 2 u + 34
5 u - 2 u = 34 - 25
3 u = 9
1 u = 9 ÷ 3 = 3
Value of $10-notes left
= 5 u x 10
= 5 x 3 x 10
= $150
Value of $20-notes left
= 2 u x 20
= 2 x 3 x 20
= $120
Value of notes left
= 150 + 120
= $270
Answer(s): $270
