Irene had a total of 145 pieces of $100 and $5 notes at first. She spent
38 of the number of $100 notes and received another 11 pieces of $5 notes from her mother. After that, the number of $5 notes she had was
12 of the remaining notes. How much money did Irene have at first?
|
$100 |
$5 |
Total |
Before |
8 u |
5 u - 11 |
145 |
Change |
- 3 u |
+ 11 |
|
After |
5 u |
|
|
Comparing $100-notes and $5-notes |
1x5 = 5 u |
1x5 = 5 u |
|
The number of $100-notes and $5-notes in the end is the same.
The number of $100-notes in the end is repeated. Make the number of $100-notes in the end the same. LCM of 1 and 5 is 5.
Number of notes at first
= 8 u + 5 u - 11
= 13 u - 11
13 u - 11 = 145
13 u = 145 + 11
13 u = 156
1 u = 156 ÷ 13 = 12
Number of $100-notes at first
= 8 u
= 8 x 12
= 96
Total value of $100-notes at first
= 96 x 100
= $9600
Number of $5-notes at first
= 5 u - 11
= 5 x 12 - 11
= 60 - 11
= 49
Total value of $5-notes at first
= 49 x 5
= $245
Amount that Irene had at first
= 9600 + 245
= $9845
Answer(s): $9845