In a bag of notes, the number of $20, $50 and $100 are in ratio of 5 : 7 : 3.
25 of the $20-notes and 8 $50-notes are taken out. The remaining notes are worth $7410. Find the difference between the value of $100-notes and $20-notes in the end.
| |
$20 |
$50 |
$100 |
| Before |
5 u |
7 u |
3 u |
| Change |
- 2 u |
- 8 |
|
| After |
3 u |
7 u - 8 |
3 u |
| |
$20 |
$50 |
$100 |
Total |
| Number |
3 u |
7 u - 8 |
3 u |
|
| Value |
20 |
50 |
100 |
|
| Total value |
60 u |
350 u - 400 |
300 u |
7410 |
Total value of the notes
= 60 u + 350 u - 400 + 300 u
= 710 u - 400
710 u - 400 = 7410
710 u = 7410 + 400
710 u = 7810
1 u = 7810 ÷ 710 = 11
Difference between the value of $100-notes and $20-notes in the end
= 300 u - 60 u
= 240 u
= 240 x 11
= $2640
Answer(s): $2640
