The number of $2, $10 and $20 notes in a piggy bank is in the ratio of 4 : 3 : 9. The notes are worth $2398 altogether. Find the total number of $10 and $20 notes.
| |
$2 |
$10 |
$20 |
Total |
| Number |
4 u |
3 u |
9 u |
|
| Value |
$2 |
$10 |
$20 |
|
| Total value |
8 u |
30 u |
180 u |
$2398 |
Total value of $2, $10 and $20 notes
= 8 u + 30 u + 180 u
= 218 u
218 u = 2398
1 u = 2398 ÷ 218 = 11
Number of $10 and $20 notes
= 3 u + 9 u
= 12 u
= 12 x 11
= 132
Answer(s): 132
