Jade had an equal number of $100 and $1 notes. After spending 28 pieces of $1 and 21 pieces of $100 notes, the ratio of the $100 notes to $1 notes left was 8 : 1. Find the value of the notes left.
| |
$100 |
$1 |
| Before |
8 u + 21 |
1 u + 28 |
| Change |
- 21 |
- 28 |
| After |
8 u |
1 u |
Number of $100 notes at first = 8 u + 21
Number of $1 notes at first = 1 u + 28
The number of $100 and $1 notes at first is the same.
8 u + 21 = 1 u + 28
8 u - 1 u = 28 - 21
7 u = 7
1 u = 7 ÷ 7 = 1
Value of $100-notes left
= 8 u x 100
= 8 x 1 x 100
= $800
Value of $1-notes left
= 1 u x 1
= 1 x 1 x 1
= $1
Value of notes left
= 800 + 1
= $801
Answer(s): $801
