Last Wednesday, Oliver withdrew an equal number of $20-notes and $100-notes from the bank. After spending 127 pieces of $20-notes and 17 pieces of $100-notes, the ratio of the remaining $20-notes to $100-notes became 2 : 7.
- How many $20-notes had he left?
- What was the total value of the notes which Oliver withdrew from the bank?
| |
$20-notes |
$100-notes |
| Before |
2 u + 127 |
7 u + 17 |
| Change |
- 127 |
- 17 |
| After |
2 u |
7 u |
(a)
Oliver withdrew an equal number of $20-notes and $100-notes from the bank. So, the number of notes of each type is the same.
7 u + 17 = 2 u + 127
7 u - 2 u = 127 - 17
5 u = 110
1 u = 110 ÷ 5 = 22
Number of $20 notes that Oliver had left
= 2 u
= 2 x 22
= 44
(b)
Number of each type of notes that Oliver withdrew
= 44 + 127
= 171
Value of one set of $20-note and 100-note
= 20 + 100
= $120
Total value of the notes that Oliver withdrew
= 120 x 171
= $20520
Answer(s): (a) 44; (b) $20520
