In a pouch of notes, the number of $2, $5 and $10 are in ratio of 2 : 2 : 7.
12 of the $2-notes is taken out and another 6 $5-notes are added. The remaining notes are worth $358. Find the difference between the value of $10-notes and $2-notes in the end.
| |
$2 |
$5 |
$10 |
| Before |
2 u |
2 u |
7 u |
| Change |
- 1 u |
+ 6 |
|
| After |
1 u |
2 u + 6 |
7 u |
| |
$2 |
$5 |
$10 |
Total |
| Number |
1 u |
2 u + 6 |
7 u |
|
| Value |
2 |
5 |
10 |
|
| Total value |
2 u |
10 u + 30 |
70 u |
358 |
Total value of the notes
= 2 u + 10 u + 30 + 70 u
= 82 u + 30
82 u + 30 = 358
82 u = 358 - 30
82 u = 328
1 u = 328 ÷ 82 = 4
Difference between the value of $10-notes and $2-notes in the end
= 70 u - 2 u
= 68 u
= 68 x 4
= $272
Answer(s): $272
