In an envelope, there were a total of 120 notes. 30% of them were $10-notes. The rest were $100-notes. Asher took out some $10-notes. As a result, the remaining $10-notes made up 20% of the notes left in the envelope. Find the total value of the $10-notes Asher took out from the envelope.
|
$10 |
$100 |
Total |
Before |
3x4 = 12 u |
7x4 = 28 u |
10x4 = 40 u |
Change |
- ? |
|
|
After |
1x7 = 7 u |
4x7 = 28 u |
5x7 = 35 u |
30% =
30100 =
310
20% =
20100 =
15
The number of $100-notes remains unchanged. Make the number of $100-notes the same. LCM of 7 and 4 is 28.
Total number of notes at first = 40 u
40 u = 120
1 u = 120 ÷ 40 = 3
Number of $10-notes that Asher took out from the envelope
= 12 u - 7 u
= 5 u
= 5 x 3
= 15
Total value of $10-notes taken out
= 15 x 10
= $150
Answer(s): $150