Last Tuesday, Ethan withdrew an equal number of $20-notes and $100-notes from the bank. After spending 71 pieces of $20-notes and 25 pieces of $100-notes, the ratio of the remaining $20-notes to $100-notes became 3 : 5.
- How many $20-notes had he left?
- What was the total value of the notes which Ethan withdrew from the bank?
|
$20-notes |
$100-notes |
Before |
3 u + 71 |
5 u + 25 |
Change |
- 71 |
- 25 |
After |
3 u |
5 u |
(a)
Ethan withdrew an equal number of $20-notes and $100-notes from the bank. So, the number of notes of each type is the same.
5 u + 25 = 3 u + 71
5 u - 3 u = 71 - 25
2 u = 46
1 u = 46 ÷ 2 = 23
Number of $20 notes that Ethan had left
= 3 u
= 3 x 23
= 69
(b)
Number of each type of notes that Ethan withdrew
= 69 + 71
= 140
Value of one set of $20-note and 100-note
= 20 + 100
= $120
Total value of the notes that Ethan withdrew
= 120 x 140
= $16800
Answer(s): (a) 69; (b) $16800