In a pouch of notes, the number of $5, $10 and $100 are in ratio of 7 : 8 : 3.
17 of the $5-notes and 15 $10-notes are taken out. The remaining notes are worth $1080. Find the difference between the value of $100-notes and $5-notes in the end.
| |
$5 |
$10 |
$100 |
| Before |
7 u |
8 u |
3 u |
| Change |
- 1 u |
- 15 |
|
| After |
6 u |
8 u - 15 |
3 u |
| |
$5 |
$10 |
$100 |
Total |
| Number |
6 u |
8 u - 15 |
3 u |
|
| Value |
5 |
10 |
100 |
|
| Total value |
30 u |
80 u - 150 |
300 u |
1080 |
Total value of the notes
= 30 u + 80 u - 150 + 300 u
= 410 u - 150
410 u - 150 = 1080
410 u = 1080 + 150
410 u = 1230
1 u = 1230 ÷ 410 = 3
Difference between the value of $100-notes and $5-notes in the end
= 300 u - 30 u
= 270 u
= 270 x 3
= $810
Answer(s): $810
