Yes, these are basic, but I'm confident you'll find additional tricks. Plus, if you don't know about 3D formulas, this is a great intro!
Text00:40 The Sum(), Count(), and Average() functions have the same arguments: numbers and values. Simply reference or input numbers or values as arguments, and let the functions calculate - Sum, Count, or Average - the results. Regarding the Count() function, remember that it only counts cells with values, no text. Check out all the different ways to input values in the GIF or video.
04:55 3D Formulas are multi-dimensional formulas that can Sum(), Count(), or Average() across multiple worksheets. To break it down, think of one worksheet and a selection of one column and multiple rows (say 'Sheet1!A1:A5') as 1D. Next, think of one worksheet and a selection of multiple columns and multiple rows (say 'Sheet1!A1:E5') as 2D. Finally, think of multiple worksheets and a selection of multiple columns and multiple rows (say 'Sheet1:Sheet5!A1:E5') as 3D. Excel will Sum(), Count(), or Average() (among other possible functions) all values or numbers on cells A1:E5 on worksheets between Sheet1 and Sheet5.
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Math-Outlines-1.xlsx