In a bag of notes, the number of $2, $10 and $20 are in ratio of 3 : 4 : 5.
13 of the $2-notes is taken out and another 6 $10-notes are added. The remaining notes are worth $924. Find the difference between the value of $20-notes and $2-notes in the end.
| |
$2 |
$10 |
$20 |
| Before |
3 u |
4 u |
5 u |
| Change |
- 1 u |
+ 6 |
|
| After |
2 u |
4 u + 6 |
5 u |
| |
$2 |
$10 |
$20 |
Total |
| Number |
2 u |
4 u + 6 |
5 u |
|
| Value |
2 |
10 |
20 |
|
| Total value |
4 u |
40 u + 60 |
100 u |
924 |
Total value of the notes
= 4 u + 40 u + 60 + 100 u
= 144 u + 60
144 u + 60 = 924
144 u = 924 - 60
144 u = 864
1 u = 864 ÷ 144 = 6
Difference between the value of $20-notes and $2-notes in the end
= 100 u - 4 u
= 96 u
= 96 x 6
= $576
Answer(s): $576
