Julie had a total of 60 pieces of $50 and $20 notes at first. She spent
57 of the number of $50 notes and received another 12 pieces of $20 notes from her mother. After that, the number of $20 notes she had was
12 of the remaining notes. How much money did Julie have at first?
|
$50 |
$20 |
Total |
Before |
7 u |
2 u - 12 |
60 |
Change |
- 5 u |
+ 12 |
|
After |
2 u |
|
|
Comparing $50-notes and $20-notes |
1x2 = 2 u |
1x2 = 2 u |
|
The number of $50-notes and $20-notes in the end is the same.
The number of $50-notes in the end is repeated. Make the number of $50-notes in the end the same. LCM of 1 and 2 is 2.
Number of notes at first
= 7 u + 2 u - 12
= 9 u - 12
9 u - 12 = 60
9 u = 60 + 12
9 u = 72
1 u = 72 ÷ 9 = 8
Number of $50-notes at first
= 7 u
= 7 x 8
= 56
Total value of $50-notes at first
= 56 x 50
= $2800
Number of $20-notes at first
= 2 u - 12
= 2 x 8 - 12
= 16 - 12
= 4
Total value of $20-notes at first
= 4 x 20
= $80
Amount that Julie had at first
= 2800 + 80
= $2880
Answer(s): $2880