In a bag of notes, the number of $2, $10 and $20 are in ratio of 5 : 7 : 1.
15 of the $2-notes and 13 $10-notes are taken out. The remaining notes are worth $948. Find the difference between the value of $20-notes and $2-notes in the end.
| |
$2 |
$10 |
$20 |
| Before |
5 u |
7 u |
1 u |
| Change |
- 1 u |
- 13 |
|
| After |
4 u |
7 u - 13 |
1 u |
| |
$2 |
$10 |
$20 |
Total |
| Number |
4 u |
7 u - 13 |
1 u |
|
| Value |
2 |
10 |
20 |
|
| Total value |
8 u |
70 u - 130 |
20 u |
948 |
Total value of the notes
= 8 u + 70 u - 130 + 20 u
= 98 u - 130
98 u - 130 = 948
98 u = 948 + 130
98 u = 1078
1 u = 1078 ÷ 98 = 11
Difference between the value of $20-notes and $2-notes in the end
= 20 u - 8 u
= 12 u
= 12 x 11
= $132
Answer(s): $132
