Anna had some $5-notes and some $1-notes.
38 of the-notes were $5-notes and the rest were $1-notes. After Anna had spent $64 worth of $1-notes and
23 of $5-notes, she had
14 of the notes left. Find the number of $5-notes Anna had left.
| |
$5-notes |
$1-notes |
Total |
Comparing $5-notes
and $1-notes
at first |
3x1 =
3 u |
5x1 =
5 u |
8x1 =
8 u |
| Before |
3x1 =
3 u |
|
4x2 =
8 u |
| Change |
- 2x1 =
- 2 u |
- 64 |
- 3x2 =
- 6 u |
| After |
1x1=
1 u |
5 u - 64 |
1x2 =
2 u |
The total number of notes at first is the repeated. Make the total number of notes the same. LCM of 8 and 4 is 8.
The number of $5-notes is repeated.
Number of $1-notes
= 64 ÷ 1
= 64
Total number of notes spent = 2 u + 64
2 u + 64 = 6 u
6 u - 2 u = 64
4 u = 64
1 u = 64 ÷ 4 = 16
Number of $5-notes that Anna had left
= 1 u
= 1 x 16
= 16
Answer(s): 16
