Answer:
The first one is correct.
The second one is also correct!
Hope this helps :)
<u>Answer</u>:
The interest charged for this month is $7.5
<u>Step-by-step explanation:</u>
Given:
Principal = $300
Interest = 30%
Time = 1 month
To Find:
The interest charged for this month = ?
Solution:
we know that the interest charged = 
1 month can also be written as 
Substituting the values,
interest charged:
=> 
=> 
=> 
=>
=>
=>
=> 7.5
Answer: 
Step-by-step explanation:

350 divided into 20 is 170 with a remainder of 10