Just change the format to General or Number.

First, 7/12/2012 minus 5/1/2013 is 293, not 284. And 10/19/1900 does indeed
correspond to the date serial number 293 (i.e. 293 days after 12/31/1899, as
Excel counts it; Excel thinks 1900 is a leap year).

As to why Excel displayed the result as Date instead of General or Number
only in C31, who knows?

It did not happen in my test. So I suspect the cell had been formatted as
Date before you entered the formula. Anyway, these things happen all the
time: Excel tries to be helpful and intuits what format to use; but
sometimes it is wrong. We just have to make adjustment sometimes.[/quote]

I appreciate your help. When one has been using a program a lot one finds little things like different formatting, etc., that might make a difference. What I did do was to go to a column separated from these three, set up the first cell as listed in A31, the next cell as B31, and used the formula in the next cell to give me the correct result I needed -- I may have had the wrong date in my note for the spreedsheet showed 284 -- 284, copied that and pasted it into C31 and it took. Anyway, your comments helped me to know something else to look for. Thanks so much. I also thought I had put into my profile, or whereever, that I would be notified by e-mail when a reply had been made, and I did not receive the notification. I just thouht I would check. Again thanks.