In a box of notes, the number of $10, $20 and $50 are in ratio of 7 : 5 : 6.
17 of the $10-notes and 14 $20-notes are taken out. The remaining notes are worth $4780. Find the difference between the value of $50-notes and $10-notes in the end.
| |
$10 |
$20 |
$50 |
| Before |
7 u |
5 u |
6 u |
| Change |
- 1 u |
- 14 |
|
| After |
6 u |
5 u - 14 |
6 u |
| |
$10 |
$20 |
$50 |
Total |
| Number |
6 u |
5 u - 14 |
6 u |
|
| Value |
10 |
20 |
50 |
|
| Total value |
60 u |
100 u - 280 |
300 u |
4780 |
Total value of the notes
= 60 u + 100 u - 280 + 300 u
= 460 u - 280
460 u - 280 = 4780
460 u = 4780 + 280
460 u = 5060
1 u = 5060 ÷ 460 = 11
Difference between the value of $50-notes and $10-notes in the end
= 300 u - 60 u
= 240 u
= 240 x 11
= $2640
Answer(s): $2640
