[Ctrl] R Fill the cell to the right
[Ctrl] [Backspace] - To jump back up (to the active cell) specially when writing formulas
F9 Highlight parts of the formula and press F9 to see the results for each part. Make sure you press Ctrl + Z to go back or use Escape afterwards so the result of the formula is not hard-coded.
COUNT - Counts the number of cells that contain numbers
COUNTA - Counts the number of cells that are not empty
COUNTBLANK - Counts the number of empty cells in a range of cells
COUNTIFS - This function applies criteria to cells across multiple ranges and counts the number of times all criteria are met.
SUM - Adds individual values, cell references or ranges or a mix of all three.
AVERAGE - Returns the average (arithmetic mean) of the arguments.
SUMIFS - Adds all its arguments that meet multiple criteria.
AVERAGEIFS - Returns the average (arithmetic mean) of all cells that meet multiple criteria.
MIN - Returns the smallest number in a set of values.
MAX - Returns the largest value in a set of values.
MINIFS - Returns the minimum value among cells specified by a given set of conditions or criteria.
MAXIFS - Returns the maximum value among cells specified by a given set of conditions or criteria.
ROUND - Rounds a number to a specified number of digits.
ROUNDUP - Rounds a number up, away from zero.
ROUNDDOWN - Rounds a number down, toward zero.
IF - Allows you to make logical comparisons between a value and what you expect. It can have two results. The first result is if your comparison is True, the second if your comparison is False.
VLOOKUP - Looks up a specified value in one column of data and returns the corresponding value from another column.
Remember: Your downloadable course notes cover the most important points. Make sure you keep them handy.

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