In a box of notes, the number of $20, $50 and $100 are in ratio of 4 : 3 : 8.
34 of the $20-notes and 7 $50-notes are taken out. The remaining notes are worth $11290. Find the difference between the value of $100-notes and $20-notes in the end.
| |
$20 |
$50 |
$100 |
| Before |
4 u |
3 u |
8 u |
| Change |
- 3 u |
- 7 |
|
| After |
1 u |
3 u - 7 |
8 u |
| |
$20 |
$50 |
$100 |
Total |
| Number |
1 u |
3 u - 7 |
8 u |
|
| Value |
20 |
50 |
100 |
|
| Total value |
20 u |
150 u - 350 |
800 u |
11290 |
Total value of the notes
= 20 u + 150 u - 350 + 800 u
= 970 u - 350
970 u - 350 = 11290
970 u = 11290 + 350
970 u = 11640
1 u = 11640 ÷ 970 = 12
Difference between the value of $100-notes and $20-notes in the end
= 800 u - 20 u
= 780 u
= 780 x 12
= $9360
Answer(s): $9360
