Last Monday, Luis withdrew an equal number of $50-notes and $10-notes from the bank. After spending 72 pieces of $50-notes and 23 pieces of $10-notes, the ratio of the remaining $50-notes to $10-notes became 2 : 9.
- How many $50-notes had he left?
- What was the total value of the notes which Luis withdrew from the bank?
| |
$50-notes |
$10-notes |
| Before |
2 u + 72 |
9 u + 23 |
| Change |
- 72 |
- 23 |
| After |
2 u |
9 u |
(a)
Luis withdrew an equal number of $50-notes and $10-notes from the bank. So, the number of notes of each type is the same.
9 u + 23 = 2 u + 72
9 u - 2 u = 72 - 23
7 u = 49
1 u = 49 ÷ 7 = 7
Number of $50 notes that Luis had left
= 2 u
= 2 x 7
= 14
(b)
Number of each type of notes that Luis withdrew
= 14 + 72
= 86
Value of one set of $50-note and 10-note
= 50 + 10
= $60
Total value of the notes that Luis withdrew
= 60 x 86
= $5160
Answer(s): (a) 14; (b) $5160
