The number of $10, $20 and $100 notes in a piggy bank is in the ratio of 1 : 6 : 6. The notes are worth $8760 altogether. Find the total number of $10 and $20 notes.
|
$10 |
$20 |
$100 |
Total |
Number |
1 u |
6 u |
6 u |
|
Value |
$10 |
$20 |
$100 |
|
Total value |
10 u |
120 u |
600 u |
$8760 |
Total value of $10, $20 and $100 notes
= 10 u + 120 u + 600 u
= 730 u
730 u = 8760
1 u = 8760 ÷ 730 = 12
Number of $10 and $20 notes
= 1 u + 6 u
= 7 u
= 7 x 12
= 84
Answer(s): 84