Linda had some $1-notes and some $100-notes.
712 of the notes were $1-notes and the rest were $100-notes. After Linda had spent $5600 worth of $100-notes and
47 of $1-notes, she had
35 of the notes left. Find the number of $100-notes Linda had left.
| |
$1-notes |
$100-notes |
Total |
Comparing $1-notes
and $100-notes
at first |
7x5 =
35 u |
5x5 =
25 u |
12x5 =
60 u |
| Before |
7x5 =
35 u |
|
5x12 =
60 u |
| Change |
- 4x5 =
- 20 u |
- 56 |
- 2x12 =
- 24 u |
| After |
3x5=
15 u |
25 u - 56 |
3x12 =
36 u |
The total number of notes at first is the repeated. Make the total number of notes the same. LCM of 12 and 5 is 60.
The number of $1-notes is repeated.
Number of $100-notes
= 5600 ÷ 100
= 56
Total number of notes spent = 20 u + 56
20 u + 56 = 24 u
24 u - 20 u = 56
4 u = 56
1 u = 56 ÷ 4 = 14
Number of $100-notes that Linda had left
= 25 u - 56
= 25 x 14 - 56
= 294
Answer(s): 294
