1. Introduction to Formulas

Formulas are the heart of Excel. Every formula must start with an equals sign (=). Without it, Excel treats your entry as plain text.

=A1 + B1 // Adds value in Cell A1 to B1

2. The SUM Function

Instead of adding cells one by one (A1+A2+A3...), use the SUM function for ranges.

=SUM(A1:A10) // Adds all cells from A1 to A10

3. AVERAGE & COUNT

Statistical functions are just as easy.

  • AVERAGE(range): Calculates the mean.
  • COUNT(range): Counts how many cells contain numbers.
=AVERAGE(B2:B20)
=COUNT(C2:C20)

4. Absolute Referencing ($)

When you copy a formula, Excel changes the cell references automatically (Relative). To lock a cell (like a Tax Rate), use the Dollar Sign ($).

=A1 * $B$1 // B1 is locked. Even if dragged down, it stays B1.

Tip: Press F4 to toggle absolute referencing automatically!

Practice Task

Create a "Monthly Expense" sheet. List 5 items, their cost, and calculate the Total using SUM and Average Cost using AVERAGE.