The number of $10, $20 and $100 notes in a piggy bank is in the ratio of 5 : 1 : 1. The notes are worth $1870 altogether. Find the total number of $10 and $20 notes.
| |
$10 |
$20 |
$100 |
Total |
| Number |
5 u |
1 u |
1 u |
|
| Value |
$10 |
$20 |
$100 |
|
| Total value |
50 u |
20 u |
100 u |
$1870 |
Total value of $10, $20 and $100 notes
= 50 u + 20 u + 100 u
= 170 u
170 u = 1870
1 u = 1870 ÷ 170 = 11
Number of $10 and $20 notes
= 5 u + 1 u
= 6 u
= 6 x 11
= 66
Answer(s): 66
