There are 5 days ( 1-5) with a balance of 2000 5 * 2000 = 10000
There are 5 days (6-10) with a balance of 1600 5*1600 = 8000
There are 10 days (11-20) with a balance of 1350 10 * 1350 = 13500
There are 11 days (21-31) with a balance of 1550 11* 1550 =17050
10000+ 8000+13500+ 17050 = 48550
Divide this by 31 days
1566.129032
The average daily balance is 1566.13 per day