Choose a learning age 7 to 11 Years. Choose a learning track Numeracy Part 2

Learning Age: 7 to 11 Years

Learning Track: Numeracy Part 2


What are the Prime Numbers?

T o learn about prime numbers, an understanding of factors is needed.

We'll start by telling you what a prime number is, followed by some fully explained examples of finding prime numbers and then an interactive Mini-Lesson on prime numbers. We'll also tell you why prime factors are useful. Then we have a short factor quiz, which gives help when needed. Finally, we have a brief summary of prime numbers.

So let's get started... what is a prime number ?

Mini-Lesson: Prime Numbers

A PRIME NUMBER IS NUMBER THAT ONLY HAS TWO FACTORS; ITSELF AND 1.

For example, let's 'find the first 3 prime numbers'...

We can find the factors in pairs.

We'll test each number from 4 downwards to see if it divides 4 exactly.

4 / 4 = 1, because 1 x 4 = 4. So 4 and 1 are factors of 4 (A NUMBER ALWAYS HAS ITSELF AND 1 AS FACTORS)

3 does not divide 4 exactly. So 3 is not a factor of 4

2 / 2 = 2, because 2 x 2 = 4. So 2 is a factor of 4 (we don't record the 2 twice)

Now we can list the factors of 4 in decending oreder as 4, 2, 1.

Here is an example where factors would be useful...

Now, let's use a 'number line' to see the factors of a number you choose.

Line highlights the multiples and scrolls

Explanation of start and end (infinity)

Quiz

Summary

A FACTOR OF A NUMBER IS NUMBER THAT EXACTLY DIVIDES INTO THE NUMBER.

A NUMBER ALWAYS HAS ITSELF AND 1 AS FACTORS

Know how to 'list factors of a number'

EasyStreet Learning. Please Log In to Continue.

Hi. You'll need to subscribe to EasyStreetLearning.com to read this topic.
EasyStreetLearning.com is a real alternative to tuition from home tutors and other services like Kumon.
To find out what's special about our approach and how we could save you hundreds of pounds, click here.

To let your child join the learning fun right now, click here.

If you are already an EasyStreet Learning subscriber, sign-in below...

User Name:Password:
Forgotten your password ? Don't worry, click here for a reminder email.
Add Your Comment On This Page (subscribers only)

Send me an email when a new comment is posted.

Sort steps by Learning order * Topic


* Progress step-by-step at your childs' pace
.