Last Sunday, Dylan withdrew an equal number of $20-notes and $5-notes from the bank. After spending 68 pieces of $20-notes and 23 pieces of $5-notes, the ratio of the remaining $20-notes to $5-notes became 2 : 7.
- How many $20-notes had he left?
- What was the total value of the notes which Dylan withdrew from the bank?
| |
$20-notes |
$5-notes |
| Before |
2 u + 68 |
7 u + 23 |
| Change |
- 68 |
- 23 |
| After |
2 u |
7 u |
(a)
Dylan withdrew an equal number of $20-notes and $5-notes from the bank. So, the number of notes of each type is the same.
7 u + 23 = 2 u + 68
7 u - 2 u = 68 - 23
5 u = 45
1 u = 45 ÷ 5 = 9
Number of $20 notes that Dylan had left
= 2 u
= 2 x 9
= 18
(b)
Number of each type of notes that Dylan withdrew
= 18 + 68
= 86
Value of one set of $20-note and 5-note
= 20 + 5
= $25
Total value of the notes that Dylan withdrew
= 25 x 86
= $2150
Answer(s): (a) 18; (b) $2150
