Numbers and Math

Numbers are used in almost every Python program. You will use them for calculations, scores, prices, measurements, statistics, and much more. Python makes working with numbers simple and powerful.

Number Types

Python mainly uses two number types:

• int for whole numbers
• float for decimal numbers

age = 25
price = 19.99

Basic Math Operators

Python supports common mathematical operations.

print(10 + 5)
print(10 - 5)
print(10 * 5)
print(10 / 5)

More Operators

print(10 // 3)
print(10 % 3)
print(2 ** 3)

Operator Meaning

• // floor division
• % remainder (modulus)
• ** power

Order of Operations

Python follows standard math rules.

print(2 + 3 * 4)
print((2 + 3) * 4)

Useful Number Functions

print(abs(-7))
print(round(3.75))
print(max(4, 8, 2))
print(min(4, 8, 2))

Working With User Input

Input is stored as text, so convert when needed.

age = int(input("Enter age: "))
print(age + 1)

Code Along

num1 = 12
num2 = 5

print(num1 + num2)
print(num1 - num2)
print(num1 * num2)
print(num1 / num2)

Mini Challenge

Create a program that:

• Stores two numbers
• Prints their sum
• Prints their difference
• Prints their product
• Prints their remainder

Real World Use Case

Shopping systems use numbers to calculate totals, taxes, discounts, and change. Banking apps use numbers for balances, transfers, and reports.

Quiz

1. What type stores decimal numbers?
2. What does % return?
3. What is the result of 2 ** 4?
4. Why do we convert input with int()?

Assignment

Build a simple calculator that asks the user for two numbers and displays results for all major operators.

Summary

You learned number types, math operators, useful number functions, operator precedence, and how to use numbers in real Python programs.