A jar contained $50 and $20 notes with a total value of $1540. 10 pieces of $20 were exchanged for $50 notes of similar value. In the end, the number of $50 notes was the same as the $20 notes. How many $50 notes were there at first?
| |
$50 |
$20 |
| Before |
1 u - 4 |
1 u + 10 |
| Change |
+ 4 |
- 10 |
| After |
1 u |
1 u |
Total value of $50 and $20 notes remains unchanged after the exchange of notes of similar value.
Total value of 10 pieces of $20-notes
= 10 x 20
= $200
Number of $50-notes that 10 pieces of $20-notes were exchanged for
= 200 ÷ 50
= 4
| In the end |
$50 |
$20 |
Total |
| Number |
1 u |
1 u |
2 u |
| Value |
50 |
20 |
|
| Total Value |
50 u |
20 u |
70 u |
Total value of $50 and $20 notes
= 50 u + 20 u
= 70 u
70 u = 1540
1 u = 1540 ÷ 70 = 22
Number of $50 notes at first
= 1 u - 4
= 22 - 4
= 18
Answer(s): 18
