In an envelope, there were a total of 140 notes. 60% of them were $2-notes. The rest were $100-notes. Peter took out some $2-notes. As a result, the remaining $2-notes made up 30% of the notes left in the envelope. Find the total value of the $2-notes Peter took out from the envelope.
| |
$2 |
$100 |
Total |
| Before |
3x7 =
21 u |
2x7 =
14 u |
5x7 =
35 u |
| Change |
- ? |
|
|
| After |
3x2 =
6 u |
7x2 =
14 u |
10x2 =
20 u |
60% =
60100 =
35
30% =
30100 =
310
The number of $100-notes remains unchanged. Make the number of $100-notes the same. LCM of 2 and 7 is 14.
Total number of notes at first = 35 u
35 u = 140
1 u = 140 ÷ 35 = 4
Number of $2-notes that Peter took out from the envelope
= 21 u - 6 u
= 15 u
= 15 x 4
= 60
Total value of $2-notes taken out
= 60 x 2
= $120
Answer(s): $120
