Using the average daily balance method and the information given, find the credit card finance charge for the month of August (31 days). The annual interest rate is 18%.

Question

Using the average daily balance method and the information​ given, find the credit card finance charge for the month of August​ (31 days). The annual interest rate is​ 18%.

July 31st (Balance) $590 
August 5 (Charge) $90 
August 9 (Payment)$560 
August 14 (Charge)$193 
August 24 (Charge)$41

I do not know how to do this. I know I am using I=PRT. However, I am getting my answers wrong.

Aug.5-8 (590+90=680)3*680=2040 
Aug.9-13 (680-560=$120)4*120=480 
Aug.14-23 (120+193-$313)9*313=2817 
Aug.24-24 (313+41=$354) 1*354

Second part 
2040+480+2817+354=5691 
5691/31(days)=183.6 (Round to nearest cent)

Third Part

I=PRT

183.6*.18*31/365=2.8068 (Round to nearest cent)

Final Answer that I got was 2.80

However, this is incorrect. I am not sure what I am doing wrong.

Reiny · Answer

I am not familiar with the "average daily balance method " , I don't live in the US. Perhaps one of the other math tutors can help out here.

Derek · Answer

Alright, thank you for your response!

Using the average daily balance method and the information​ given, find the credit card finance charge for the month of August​ (31 days). The annual interest rate is​ 18%.

Using the average daily balance method and the information given, find the credit card finance charge for the month of August (31 days). The annual interest rate is 18%.