Mary had an equal number of $1 and $2 notes. After spending 30 pieces of $2 and 26 pieces of $1 notes, the ratio of the $1 notes to $2 notes left was 7 : 5. Find the value of the notes left.
| |
$1 |
$2 |
| Before |
7 u + 26 |
5 u + 30 |
| Change |
- 26 |
- 30 |
| After |
7 u |
5 u |
Number of $1 notes at first = 7 u + 26
Number of $2 notes at first = 5 u + 30
The number of $1 and $2 notes at first is the same.
7 u + 26 = 5 u + 30
7 u - 5 u = 30 - 26
2 u = 4
1 u = 4 ÷ 2 = 2
Value of $1-notes left
= 7 u x 1
= 7 x 2 x 1
= $14
Value of $2-notes left
= 5 u x 2
= 5 x 2 x 2
= $20
Value of notes left
= 14 + 20
= $34
Answer(s): $34
