Eva had an equal number of $100 and $20 notes. After spending 37 pieces of $20 and 12 pieces of $100 notes, the ratio of the $100 notes to $20 notes left was 6 : 1. Find the value of the notes left.
| |
$100 |
$20 |
| Before |
6 u + 12 |
1 u + 37 |
| Change |
- 12 |
- 37 |
| After |
6 u |
1 u |
Number of $100 notes at first = 6 u + 12
Number of $20 notes at first = 1 u + 37
The number of $100 and $20 notes at first is the same.
6 u + 12 = 1 u + 37
6 u - 1 u = 37 - 12
5 u = 25
1 u = 25 ÷ 5 = 5
Value of $100-notes left
= 6 u x 100
= 6 x 5 x 100
= $3000
Value of $20-notes left
= 1 u x 20
= 1 x 5 x 20
= $100
Value of notes left
= 3000 + 100
= $3100
Answer(s): $3100
