Hazel had some $5-notes and some $10-notes.
811 of the-notes were $5-notes and the rest were $10-notes. After Hazel had spent $4400 worth of $10-notes and
58 of $5-notes, she had
27 of the notes left. Find the number of $5-notes Hazel had left.
| |
$5-notes |
$10-notes |
Total |
Comparing $5-notes
and $10-notes
at first |
8x7 =
56 u |
3x7 =
21 u |
11x7 =
77 u |
| Before |
8x7 =
56 u |
|
7x11 =
77 u |
| Change |
- 5x7 =
- 35 u |
- 440 |
- 5x11 =
- 55 u |
| After |
3x7=
21 u |
21 u - 440 |
2x11 =
22 u |
The total number of notes at first is the repeated. Make the total number of notes the same. LCM of 11 and 7 is 77.
The number of $5-notes is repeated.
Number of $10-notes
= 4400 ÷ 10
= 440
Total number of notes spent = 35 u + 440
35 u + 440 = 55 u
55 u - 35 u = 440
20 u = 440
1 u = 440 ÷ 20 = 22
Number of $5-notes that Hazel had left
= 21 u
= 21 x 22
= 462
Answer(s): 462
