Natalie had some $50-notes and some $100-notes.
49 of the-notes were $50-notes and the rest were $100-notes. After Natalie had spent $6800 worth of $100-notes and
14 of $50-notes, she had
45 of the notes left. Find the number of $50-notes Natalie had left.
| |
$50-notes |
$100-notes |
Total |
Comparing $50-notes
and $100-notes
at first |
4x5 =
20 u |
5x5 =
25 u |
9x5 =
45 u |
| Before |
4x5 =
20 u |
|
5x9 =
45 u |
| Change |
- 1x5 =
- 5 u |
- 68 |
- 1x9 =
- 9 u |
| After |
3x5=
15 u |
25 u - 68 |
4x9 =
36 u |
The total number of notes at first is the repeated. Make the total number of notes the same. LCM of 9 and 5 is 45.
The number of $50-notes is repeated.
Number of $100-notes
= 6800 ÷ 100
= 68
Total number of notes spent = 5 u + 68
5 u + 68 = 9 u
9 u - 5 u = 68
4 u = 68
1 u = 68 ÷ 4 = 17
Number of $50-notes that Natalie had left
= 15 u
= 15 x 17
= 255
Answer(s): 255
