In a pouch of notes, the number of $10, $50 and $100 are in ratio of 3 : 7 : 8.
13 of the $10-notes is taken out and another 4 $50-notes are added. The remaining notes are worth $8390. Find the difference between the value of $100-notes and $10-notes in the end.
| |
$10 |
$50 |
$100 |
| Before |
3 u |
7 u |
8 u |
| Change |
- 1 u |
+ 4 |
|
| After |
2 u |
7 u + 4 |
8 u |
| |
$10 |
$50 |
$100 |
Total |
| Number |
2 u |
7 u + 4 |
8 u |
|
| Value |
10 |
50 |
100 |
|
| Total value |
20 u |
350 u + 200 |
800 u |
8390 |
Total value of the notes
= 20 u + 350 u + 200 + 800 u
= 1170 u + 200
1170 u + 200 = 8390
1170 u = 8390 - 200
1170 u = 8190
1 u = 8190 ÷ 1170 = 7
Difference between the value of $100-notes and $10-notes in the end
= 800 u - 20 u
= 780 u
= 780 x 7
= $5460
Answer(s): $5460
