Last Friday, Bobby withdrew an equal number of $10-notes and $50-notes from the bank. After spending 77 pieces of $10-notes and 14 pieces of $50-notes, the ratio of the remaining $10-notes to $50-notes became 2 : 5.
- How many $10-notes had he left?
- What was the total value of the notes which Bobby withdrew from the bank?
| |
$10-notes |
$50-notes |
| Before |
2 u + 77 |
5 u + 14 |
| Change |
- 77 |
- 14 |
| After |
2 u |
5 u |
(a)
Bobby withdrew an equal number of $10-notes and $50-notes from the bank. So, the number of notes of each type is the same.
5 u + 14 = 2 u + 77
5 u - 2 u = 77 - 14
3 u = 63
1 u = 63 ÷ 3 = 21
Number of $10 notes that Bobby had left
= 2 u
= 2 x 21
= 42
(b)
Number of each type of notes that Bobby withdrew
= 42 + 77
= 119
Value of one set of $10-note and 50-note
= 10 + 50
= $60
Total value of the notes that Bobby withdrew
= 60 x 119
= $7140
Answer(s): (a) 42; (b) $7140
