Zara had an equal number of $100 and $5 notes. After spending 42 pieces of $5 and 34 pieces of $100 notes, the ratio of the $100 notes to $5 notes left was 7 : 5. Find the value of the notes left.
| |
$100 |
$5 |
| Before |
7 u + 34 |
5 u + 42 |
| Change |
- 34 |
- 42 |
| After |
7 u |
5 u |
Number of $100 notes at first = 7 u + 34
Number of $5 notes at first = 5 u + 42
The number of $100 and $5 notes at first is the same.
7 u + 34 = 5 u + 42
7 u - 5 u = 42 - 34
2 u = 8
1 u = 8 ÷ 2 = 4
Value of $100-notes left
= 7 u x 100
= 7 x 4 x 100
= $2800
Value of $5-notes left
= 5 u x 5
= 5 x 4 x 5
= $100
Value of notes left
= 2800 + 100
= $2900
Answer(s): $2900
