Basic Math in Cells (+, -, *, /, Parentheses)

Why This Feature Matters

At its heart, a spreadsheet is a giant, super-fast visual calculator. You don't always need complex formulas to get work done—everyday business calculations like multiplying prices, subtracting discounts, or adding taxes can be done directly using standard math signs: plus (+), minus (-), multiply (*), and divide (/).

Whenever you start a cell with an equals sign (=), you tell Excel to calculate the numbers instead of treating them as plain text. If any of the original numbers change later, your calculation updates instantly!

How Math Works in Spreadsheets

Spreadsheets follow the standard order of operations: multiplication and division happen before addition and subtraction. If you want a specific step to happen first (like adding numbers before multiplying), simply wrap that step inside parentheses ( ).

Step-by-Step Practice Guide

Follow these steps to calculate final invoice totals for four hardware items in your table:

Practice 1 — Simple Multiplication (Laptop Pro)

Calculate the gross total by multiplying Unit Price (B2) by Quantity (C2) in cell F2.

=B2*C2

Practice 2 — Subtracting a Discount (Wireless Mouse)

Multiply Unit Price (B3) by Quantity (C3) inside parentheses, then subtract the flat discount in cell D3.

=(B3*C3)-D3

Practice 3 — Adding Tax (4K Monitor)

Multiply gross total by (1 + E4) to add the 8% tax rate in cell F4.

=(B4*C4)*(1+E4)

Practice 4 — Discount First, Then Tax (Keyboard)

First calculate the discounted amount ((B5*C5)-D5), then multiply the result by (1+E5) to add tax in cell F5.

=((B5*C5)-D5)*(1+E5)

Always use parentheses whenever you combine addition or subtraction with multiplication. It makes your formula easy to read for anyone on your team and guarantees accurate math every time.