In a pouch of notes, the number of $2, $5 and $20 are in ratio of 5 : 4 : 8.
15 of the $2-notes is taken out and another 2 $5-notes are added. The remaining notes are worth $386. Find the difference between the value of $20-notes and $2-notes in the end.
| |
$2 |
$5 |
$20 |
| Before |
5 u |
4 u |
8 u |
| Change |
- 1 u |
+ 2 |
|
| After |
4 u |
4 u + 2 |
8 u |
| |
$2 |
$5 |
$20 |
Total |
| Number |
4 u |
4 u + 2 |
8 u |
|
| Value |
2 |
5 |
20 |
|
| Total value |
8 u |
20 u + 10 |
160 u |
386 |
Total value of the notes
= 8 u + 20 u + 10 + 160 u
= 188 u + 10
188 u + 10 = 386
188 u = 386 - 10
188 u = 376
1 u = 376 ÷ 188 = 2
Difference between the value of $20-notes and $2-notes in the end
= 160 u - 8 u
= 152 u
= 152 x 2
= $304
Answer(s): $304
