The number of $5, $50 and $100 notes in a piggy bank is in the ratio of 4 : 7 : 7. The notes are worth $6420 altogether. Find the total number of $50 and $100 notes.
| |
$5 |
$50 |
$100 |
Total |
| Number |
4 u |
7 u |
7 u |
|
| Value |
$5 |
$50 |
$100 |
|
| Total value |
20 u |
350 u |
700 u |
$6420 |
Total value of $5, $50 and $100 notes
= 20 u + 350 u + 700 u
= 1070 u
1070 u = 6420
1 u = 6420 ÷ 1070 = 6
Number of $50 and $100 notes
= 7 u + 7 u
= 14 u
= 14 x 6
= 84
Answer(s): 84
