Cindy had an equal number of $2 and $5 notes. After spending 21 pieces of $5 and 19 pieces of $2 notes, the ratio of the $2 notes to $5 notes left was 3 : 1. Find the value of the notes left.
| |
$2 |
$5 |
| Before |
3 u + 19 |
1 u + 21 |
| Change |
- 19 |
- 21 |
| After |
3 u |
1 u |
Number of $2 notes at first = 3 u + 19
Number of $5 notes at first = 1 u + 21
The number of $2 and $5 notes at first is the same.
3 u + 19 = 1 u + 21
3 u - 1 u = 21 - 19
2 u = 2
1 u = 2 ÷ 2 = 1
Value of $2-notes left
= 3 u x 2
= 3 x 1 x 2
= $6
Value of $5-notes left
= 1 u x 5
= 1 x 1 x 5
= $5
Value of notes left
= 6 + 5
= $11
Answer(s): $11
