In a bag of notes, the number of $5, $10 and $20 are in ratio of 5 : 3 : 4.
25 of the $5-notes and 11 $10-notes are taken out. The remaining notes are worth $765. Find the difference between the value of $20-notes and $5-notes in the end.
| |
$5 |
$10 |
$20 |
| Before |
5 u |
3 u |
4 u |
| Change |
- 2 u |
- 11 |
|
| After |
3 u |
3 u - 11 |
4 u |
| |
$5 |
$10 |
$20 |
Total |
| Number |
3 u |
3 u - 11 |
4 u |
|
| Value |
5 |
10 |
20 |
|
| Total value |
15 u |
30 u - 110 |
80 u |
765 |
Total value of the notes
= 15 u + 30 u - 110 + 80 u
= 125 u - 110
125 u - 110 = 765
125 u = 765 + 110
125 u = 875
1 u = 875 ÷ 125 = 7
Difference between the value of $20-notes and $5-notes in the end
= 80 u - 15 u
= 65 u
= 65 x 7
= $455
Answer(s): $455
