Last Tuesday, Billy withdrew an equal number of $5-notes and $10-notes from the bank. After spending 40 pieces of $5-notes and 26 pieces of $10-notes, the ratio of the remaining $5-notes to $10-notes became 5 : 7.
- 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 + 40 |
7 u + 26 |
Change |
- 40 |
- 26 |
After |
5 u |
7 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.
7 u + 26 = 5 u + 40
7 u - 5 u = 40 - 26
2 u = 14
1 u = 14 ÷ 2 = 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 + 40
= 75
Value of one set of $5-note and 10-note
= 5 + 10
= $15
Total value of the notes that Billy withdrew
= 15 x 75
= $1125
Answer(s): (a) 35; (b) $1125