# Numbers and operations

Contents

Math is all about numbers (like 89 and 3.14) and operations (like addition and multiplication). In these tutorials, we learn about a some new types of numbers and some new types of operations.

See how you score on these 20 practice questions

Learn how to convert between repeating decimals and fractions.

A strong contender for coolest symbol in mathematics is the radical. What is it? How does it relate to exponents? How is the square root different than the cube root? Learn all about square roots and cube roots in this tutorial.

Learn what irrational numbers are. Also learn how to classify numbers as whole, integer, rational, and irrational.

The values of irrational numbers can't be written perfectly as decimals or fractions. However, we can approximate them, which is usually good enough. In this tutorial, we learn how to approximate and compare irrational numbers.

Learn the rules for simplifying exponent expressions.

It's normally a bad idea to hang around with negative people or do negative things, but we think it's OK to associate with negative exponents. As a matter of fact, we'll learn that positive and negative exponents have quite the opposite effect on their bases.

Practice using the exponent properties to rewrite powers, where the exponent can either be positive or negative.

This tutorial leads in to scientific notation. It features multiplication and division problems involving powers of 10.

Scientists and engineers often deal with super huge numbers like 6,000,000,000,000,000,000,000 and super small numbers like 0.0000000000532. How can they do this without tiring their hands out? How can they look at a number and understand how large or small it is without counting the digits? The answer to both questions: scientific notation.

Solve multiplication, division, addition, and subtraction problems involving numbers written in scientific notation.