The number of $2, $10 and $20 notes in a piggy bank is in the ratio of 2 : 5 : 8. The notes are worth $1284 altogether. Find the total number of $10 and $20 notes.
|
$2 |
$10 |
$20 |
Total |
Number |
2 u |
5 u |
8 u |
|
Value |
$2 |
$10 |
$20 |
|
Total value |
4 u |
50 u |
160 u |
$1284 |
Total value of $2, $10 and $20 notes
= 4 u + 50 u + 160 u
= 214 u
214 u = 1284
1 u = 1284 ÷ 214 = 6
Number of $10 and $20 notes
= 5 u + 8 u
= 13 u
= 13 x 6
= 78
Answer(s): 78