In the time of smartphones and tablets, almost everyone has a calculator within arm’s reach. But what happens when you don’t? How will you calculate basic arithmetic on the fly? Learn a few of these mental math tricks to improve your math skill and impress your friends.

*For more advice and help with math, visit Noodle’s math topic page!*

## Quickly Multiply Numbers by 11

Use this quick and dirty tip to quickly multiply double digit numbers by 11.

## Calculate Tips at Blazing Speed

Ready to get out of the restaurant? Try this trick to calculate tip quickly.

## Mental Math’s Most Precious Secret

Find out one of the most important tricks in mental math.

## Adding Up Single Digit Numbers

Think you can add quickly? Try using this technique to add faster.

## Adding Up Double Digit Numbers

Double down on addition, and quickly add double digit numbers in your head.

## Add Up Money

Don’t ever get short-changed again by figuring out this mental math skill.