Linda had some $100-notes and some $2-notes.
23 of the-notes were $100-notes and the rest were $2-notes. After Linda had spent $294 worth of $2-notes and
12 of $100-notes, she had
511 of the notes left. Find the number of $100-notes Linda had left.
| |
$100-notes |
$2-notes |
Total |
Comparing $100-notes
and $2-notes
at first |
2x11 =
22 u |
1x11 =
11 u |
3x11 =
33 u |
| Before |
2x11 =
22 u |
|
11x3 =
33 u |
| Change |
- 1x11 =
- 11 u |
- 147 |
- 6x3 =
- 18 u |
| After |
1x11=
11 u |
11 u - 147 |
5x3 =
15 u |
The total number of notes at first is the repeated. Make the total number of notes the same. LCM of 3 and 11 is 33.
The number of $100-notes is repeated.
Number of $2-notes
= 294 ÷ 2
= 147
Total number of notes spent = 11 u + 147
11 u + 147 = 18 u
18 u - 11 u = 147
7 u = 147
1 u = 147 ÷ 7 = 21
Number of $100-notes that Linda had left
= 11 u
= 11 x 21
= 231
Answer(s): 231
