In a box of notes, the number of $2, $5 and $20 are in ratio of 5 : 6 : 6.
15 of the $2-notes is taken out and another 3 $5-notes are added. The remaining notes are worth $331. Find the difference between the value of $20-notes and $2-notes in the end.
|
$2 |
$5 |
$20 |
Before |
5 u |
6 u |
6 u |
Change |
- 1 u |
+ 3 |
|
After |
4 u |
6 u + 3 |
6 u |
|
$2 |
$5 |
$20 |
Total |
Number |
4 u |
6 u + 3 |
6 u |
|
Value |
2 |
5 |
20 |
|
Total value |
8 u |
30 u + 15 |
120 u |
331 |
Total value of the notes
= 8 u + 30 u + 15 + 120 u
= 158 u + 15
158 u + 15 = 331
158 u = 331 - 15
158 u = 316
1 u = 316 ÷ 158 = 2
Difference between the value of $20-notes and $2-notes in the end
= 120 u - 8 u
= 112 u
= 112 x 2
= $224
Answer(s): $224