In a pouch of notes, the number of $2, $5 and $20 are in ratio of 7 : 2 : 2.
27 of the $2-notes is taken out and another 5 $5-notes are added. The remaining notes are worth $505. Find the difference between the value of $20-notes and $2-notes in the end.
|
$2 |
$5 |
$20 |
Before |
7 u |
2 u |
2 u |
Change |
- 2 u |
+ 5 |
|
After |
5 u |
2 u + 5 |
2 u |
|
$2 |
$5 |
$20 |
Total |
Number |
5 u |
2 u + 5 |
2 u |
|
Value |
2 |
5 |
20 |
|
Total value |
10 u |
10 u + 25 |
40 u |
505 |
Total value of the notes
= 10 u + 10 u + 25 + 40 u
= 60 u + 25
60 u + 25 = 505
60 u = 505 - 25
60 u = 480
1 u = 480 ÷ 60 = 8
Difference between the value of $20-notes and $2-notes in the end
= 40 u - 10 u
= 30 u
= 30 x 8
= $240
Answer(s): $240