Last Wednesday, Bobby withdrew an equal number of $50-notes and $20-notes from the bank. After spending 61 pieces of $50-notes and 13 pieces of $20-notes, the ratio of the remaining $50-notes to $20-notes became 5 : 7.
- How many $50-notes had he left?
- What was the total value of the notes which Bobby withdrew from the bank?
|
$50-notes |
$20-notes |
Before |
5 u + 61 |
7 u + 13 |
Change |
- 61 |
- 13 |
After |
5 u |
7 u |
(a)
Bobby withdrew an equal number of $50-notes and $20-notes from the bank. So, the number of notes of each type is the same.
7 u + 13 = 5 u + 61
7 u - 5 u = 61 - 13
2 u = 48
1 u = 48 ÷ 2 = 24
Number of $50 notes that Bobby had left
= 5 u
= 5 x 24
= 120
(b)
Number of each type of notes that Bobby withdrew
= 120 + 61
= 181
Value of one set of $50-note and 20-note
= 50 + 20
= $70
Total value of the notes that Bobby withdrew
= 70 x 181
= $12670
Answer(s): (a) 120; (b) $12670