Help creating complex formula using ISNUMBER

[justinjevans]

Hi, I'm trying to create a grade sheet to track my students' progress. I've been searching all over and can't figure this out.

I would like to be able to see each students' grade-in-progress, according to current assignments/exams.

Here's a link to what the spreadsheet looks like:
https://1drv.ms/u/s!Ah_05qUKB0mwhpYi00jQOfaKCN906Q

In column S, I am trying to use the following formula:
=IF(ISNUMBER(N30),(N30/N31)*N32,"")+(ISNUMBER(O30),(O30/O31)*O32,"")+(ISNUMBER(P30),(P30/P31)*P32,"")+(ISNUMBER(Q30),(Q30/Q31)*Q32,"")

There are 4 columns used to calculate the final grade: N, O, P, and Q
I want column S to only use those cells which have a grade entered.

Note: Column N is the total of quiz scores listed in columns B through M

Thanks for your help!

 

[wwbwb]

Try this:

=IF(ISNUMBER(N30),(N30/N31)*N32,0)+IF(ISNUMBER(O30),(O30/O31)*O32,0)+IF(ISNUMBER(P30),(P30/P31)*P32,0)+IF(ISNUMBER(Q30),(Q30/Q31)*Q32,0)

 

[justinjevans]

That did it! Thank you so much!