The number of $5, $20 and $100 notes in a piggy bank is in the ratio of 6 : 5 : 7. The notes are worth $6640 altogether. Find the total number of $20 and $100 notes.
| |
$5 |
$20 |
$100 |
Total |
| Number |
6 u |
5 u |
7 u |
|
| Value |
$5 |
$20 |
$100 |
|
| Total value |
30 u |
100 u |
700 u |
$6640 |
Total value of $5, $20 and $100 notes
= 30 u + 100 u + 700 u
= 830 u
830 u = 6640
1 u = 6640 ÷ 830 = 8
Number of $20 and $100 notes
= 5 u + 7 u
= 12 u
= 12 x 8
= 96
Answer(s): 96
