In an envelope, there were a total of 120 notes. 40% of them were $100-notes. The rest were $1-notes. Charlie took out some $100-notes. As a result, the remaining $100-notes made up 10% of the notes left in the envelope. Find the total value of the $100-notes Charlie took out from the envelope.
|
$100 |
$1 |
Total |
Before |
2x3 = 6 u |
3x3 = 9 u |
5x3 = 15 u |
Change |
- ? |
|
|
After |
1x1 = 1 u |
9x1 = 9 u |
10x1 = 10 u |
40% =
40100 =
25
10% =
10100 =
110
The number of $1-notes remains unchanged. Make the number of $1-notes the same. LCM of 3 and 9 is 9.
Total number of notes at first = 15 u
15 u = 120
1 u = 120 ÷ 15 = 8
Number of $100-notes that Charlie took out from the envelope
= 6 u - 1 u
= 5 u
= 5 x 8
= 40
Total value of $100-notes taken out
= 40 x 100
= $4000
Answer(s): $4000