A jar contained $5 and $20 notes with a total value of $525. 9 pieces of $20 were exchanged for $5 notes of similar value. In the end, the number of $5 notes was the same as the $20 notes. How many $20 notes were there at first?
|
$5 |
$20 |
Before |
1 u - 36 |
1 u + 9 |
Change |
+ 36 |
- 9 |
After |
1 u |
1 u |
Total value of $5 and $20 notes remains unchanged after the exchange of notes of similar value.
Total value of 9 pieces of $20-notes
= 9 x 20
= $180
Number of $5-notes that 9 pieces of $20-notes were exchanged for
= 180 ÷ 5
= 36
In the end |
$5 |
$20 |
Total |
Number |
1 u |
1 u |
2 u |
Value |
5 |
20 |
|
Total Value |
5 u |
20 u |
25 u |
Total value of $5 and $20 notes
= 5 u + 20 u
= 25 u
25 u = 525
1 u = 525 ÷ 25 = 21
Number of $20 notes at first
= 1 u + 9
= 21 + 9
= 30
Answer(s): 30