The number of $5, $20 and $50 notes in a piggy bank is in the ratio of 7 : 9 : 3. The notes are worth $2555 altogether. Find the total number of $20 and $50 notes.
| |
$5 |
$20 |
$50 |
Total |
| Number |
7 u |
9 u |
3 u |
|
| Value |
$5 |
$20 |
$50 |
|
| Total value |
35 u |
180 u |
150 u |
$2555 |
Total value of $5, $20 and $50 notes
= 35 u + 180 u + 150 u
= 365 u
365 u = 2555
1 u = 2555 ÷ 365 = 7
Number of $20 and $50 notes
= 9 u + 3 u
= 12 u
= 12 x 7
= 84
Answer(s): 84
