# Factors of 10

## Introduction

Can you recite your best friend’s phone number? Probably not thanks to our cell phones where we just have to press our friend’s name and our cell phone instantly dials him. However, there was a time when we had to memorize phone numbers.

Today, I can barely remember my own. Including the area code, each phone number includes 10 numbers. In most cases, you can remember 3 numbers or things at a time. However, you can’t do that with phone numbers based on the amount of numbers that are included.

Read the number below. See if you can memorize it. How do you memorize that phone number?

So, most of the time, people can memorize the first and second set of 3 numbers, but then they must remember the last 4 numbers. Did you say all four numbers together, or did you break them down to two and two numbers? The problem is that 3 is not a factor of 10.

## Factors in Real Life with 10

Maybe we can find a better way to remember 10-digit phone numbers. Let’s first find the factors for 10.

You have two choices to make to memorize a 10-digit phone number if you want to memorize equal amounts of numbers instead of the 3-3-4 pattern that most of us use. So, you could either memorize 5 digits at once. That seems difficult.

Most research shows people can remember 3 items at once. When you get to 5 items followed by another set of 5 items, that doesn’t seem to be the best idea. Instead, let’s try memorizing the numbers in pair.

See if you can do it. Look at the random set of 10 numbers below. Try to memorize them using the pair method.

How did you do? I decided to leave off the hyphens in between the pairs of numbers to see if you would memorize that number by remembering the pairs of the numbers. Did it work?