In a pouch of notes, the number of $5, $50 and $100 are in ratio of 7 : 1 : 7.
47 of the $5-notes and 10 $50-notes are taken out. The remaining notes are worth $1030. Find the difference between the value of $100-notes and $5-notes in the end.
| |
$5 |
$50 |
$100 |
| Before |
7 u |
1 u |
7 u |
| Change |
- 4 u |
- 10 |
|
| After |
3 u |
1 u - 10 |
7 u |
| |
$5 |
$50 |
$100 |
Total |
| Number |
3 u |
1 u - 10 |
7 u |
|
| Value |
5 |
50 |
100 |
|
| Total value |
15 u |
50 u - 500 |
700 u |
1030 |
Total value of the notes
= 15 u + 50 u - 500 + 700 u
= 765 u - 500
765 u - 500 = 1030
765 u = 1030 + 500
765 u = 1530
1 u = 1530 ÷ 765 = 2
Difference between the value of $100-notes and $5-notes in the end
= 700 u - 15 u
= 685 u
= 685 x 2
= $1370
Answer(s): $1370
