In a pouch of notes, the number of $5, $10 and $50 are in ratio of 5 : 5 : 7.
45 of the $5-notes is taken out and another 15 $10-notes are added. The remaining notes are worth $960. Find the difference between the value of $50-notes and $5-notes in the end.
| |
$5 |
$10 |
$50 |
| Before |
5 u |
5 u |
7 u |
| Change |
- 4 u |
+ 15 |
|
| After |
1 u |
5 u + 15 |
7 u |
| |
$5 |
$10 |
$50 |
Total |
| Number |
1 u |
5 u + 15 |
7 u |
|
| Value |
5 |
10 |
50 |
|
| Total value |
5 u |
50 u + 150 |
350 u |
960 |
Total value of the notes
= 5 u + 50 u + 150 + 350 u
= 405 u + 150
405 u + 150 = 960
405 u = 960 - 150
405 u = 810
1 u = 810 ÷ 405 = 2
Difference between the value of $50-notes and $5-notes in the end
= 350 u - 5 u
= 345 u
= 345 x 2
= $690
Answer(s): $690
