Last Monday, Billy withdrew an equal number of $5-notes and $10-notes from the bank. After spending 50 pieces of $5-notes and 29 pieces of $10-notes, the ratio of the remaining $5-notes to $10-notes became 5 : 8.
- How many $5-notes had he left?
- What was the total value of the notes which Billy withdrew from the bank?
| |
$5-notes |
$10-notes |
| Before |
5 u + 50 |
8 u + 29 |
| Change |
- 50 |
- 29 |
| After |
5 u |
8 u |
(a)
Billy withdrew an equal number of $5-notes and $10-notes from the bank. So, the number of notes of each type is the same.
8 u + 29 = 5 u + 50
8 u - 5 u = 50 - 29
3 u = 21
1 u = 21 ÷ 3 = 7
Number of $5 notes that Billy had left
= 5 u
= 5 x 7
= 35
(b)
Number of each type of notes that Billy withdrew
= 35 + 50
= 85
Value of one set of $5-note and 10-note
= 5 + 10
= $15
Total value of the notes that Billy withdrew
= 15 x 85
= $1275
Answer(s): (a) 35; (b) $1275
