Vanessa had a total of 37 pieces of $2 and $20 notes at first. She spent
57 of the number of $2 notes and received another 8 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 Vanessa have at first?
|
$2 |
$20 |
Total |
Before |
7 u |
2 u - 8 |
37 |
Change |
- 5 u |
+ 8 |
|
After |
2 u |
|
|
Comparing $2-notes and $20-notes |
1x2 = 2 u |
1x2 = 2 u |
|
The number of $2-notes and $20-notes in the end is the same.
The number of $2-notes in the end is repeated. Make the number of $2-notes in the end the same. LCM of 1 and 2 is 2.
Number of notes at first
= 7 u + 2 u - 8
= 9 u - 8
9 u - 8 = 37
9 u = 37 + 8
9 u = 45
1 u = 45 ÷ 9 = 5
Number of $2-notes at first
= 7 u
= 7 x 5
= 35
Total value of $2-notes at first
= 35 x 2
= $70
Number of $20-notes at first
= 2 u - 8
= 2 x 5 - 8
= 10 - 8
= 2
Total value of $20-notes at first
= 2 x 20
= $40
Amount that Vanessa had at first
= 70 + 40
= $110
Answer(s): $110