"internet cafe log" spreadsheet

I just found this forum and looking to see if I can get some help for an internet log spreadsheet that I'm creating. What I have for columns are Computer, Start Time, End Time, Minutes (difference between start and end time), Printing, Food, and total. Each row under the columns will be an entry for every person who uses the computer. The rate for internet usage (minutes) is
15 = $2.50
30 = $4.75
45 = $7.00
60 = $9.00

What I'm looking for help on is finding the Minutes column calculated from the start/end time and then based on that, add the printing and food cells together and find the total of what the minutes equate to and add that printing/food together and put it in the total cell. Is this a job for Macro coding?

(End Time - Start Time) * 1440 will get you minutes.
Then you can use a VLOOKUP formula on the minutes to get the internet usage rate and add Food and Print on the end. No macro is necessary.

thanks for the reply! vlookup is helpful if I have exact usage at 15,30,45 or 60 but if I have 3 people who use 17 minutes, 41 minutes, and 72 minutes. The first person would fall in the 15 minute bracket (we have a 5 minute safety time after the time used) and charged 15 minutes worth of time. Second person would be in the 45 minute bracket, and the third person would be 1 hour and 15 minute bracket. Is there a way to check a range in a cell, like 1-20, 21-35?

You're probably using False as the last argument in the VLOOKUP. If you change that to true, it will look up against the highest value that is lower than or equal to your lookup value (e.g., if the table is by 10 minutes, looking up 22 minutes would return the value next to 20). To add your safety time just add 5 in the first argument of your VLOOKUP or after the formula I gave you (depending on whether you want it to show in the time or not).

Thanks for the help so far darkyam. The problem I'm having with vlookup is that it looks down if it can't find a matching cell. I need a function to look or "round" up to the next biggest # in a column. Is there a function that does that or a way to reverse vlookup?

The following thread has very nearly the same issue. NBVC solved it and pasted the workbook with the solution in it.
http://excelforum.com/showthread.php?t=637916
HTH