Let me try to explain why your question is confusing. In the first part of your original post, you appear to be using a decimal point for time instead of the colon that many of us are used to.
From this statement, "After 3 pay periods the accrual total is 12.60 which is actually 13 hours" I surmise that 4.20 means 4 hours 20 minutes.
Let's do the math your way:
3 * 4.20 = 12.60 or 12 hours 60 minutes or 13 hours
Most of us (including Excel) would use 4:20 for 4 hours 20 minutes. In Excel,
3 * 4:20 would equal 13.00, just like you are looking for.
Now, I guess it's OK to denote time with a decimal point method, but the problem is that you are not being consistent. This is where your method fails:
"I have a beginning accrued total of 17.20 and I use 8.30 hours. This leaves me a balance of 8.90 hours which is actually 9.30 hours"
Using your method, that would look like this:
17.20 - 8.30 = 8.90
17 hours 20 minutes minus 8 hours 30 minutes = 8 hours 90 minutes.
The problem is that 17 hours 20 minutes minus 8 hours 30 minutes is not 8 hours 90 minutes, it's actually 8 hours 50 minutes.
17:20 - 8:30 = 8:50
Since there are only 60 minutes in an hour, you can't simply subtract your decimal portion and expect the minutes to come out correctly.
If you want to use Excel to convert times for you, you either have use the standard time formats (4:20) or realize that 4.2 hours is actually 4:12 since
.20 x 60 = 12.
I hope that helps.
Click Here Before Posting Data or VBA Code ---> How To Post Data or Code.