The ratio of the number of $2-notes to $20-notes in Kathy's wallet was 1 : 5. Kathy exchanged 8 pieces of $20-notes for $2-notes. She then had an equal number of $2-notes and $20-notes. What was the total value of $2-notes and $20-notes in Kathy's wallet at first?
|
$2-notes |
$20-notes |
Before |
1 u |
5 u |
Change |
+ 80 |
- 8 |
After |
1 u + 80 |
5 u - 8 |
Value of 8 pieces of $20-notes
= 8 x 20
= $160
Number of $2-notes that Kathy exchanged for
= 160 ÷ 2
= 80
After the exchange, Kathy had an equal number of $2-notes and $20-notes.
5 u - 8 = 1 u + 80
5 u - 1 u = 80 + 8
4 u = 88
1 u = 88 ÷ 4 = 22
Number of $2-notes at first
= 1 u
= 22
Value of $2-notes at first
= 22 x 2
= $44
Number of $20-notes at first
= 5 u
= 5 x 22
= 110
Value of $20-notes at first
= 110 x 20
= $2200
Total value of $2-notes and $20-notes at first
= 44 + 2200
= $2244
Answer(s): $2244