## Pages

►This site was originally created for my kids and their cousins, because we did science together. We eventually added more friends and I ended up having science classes for five years. I am no longer adding to the site (since 2014), but will leave it up for others' use. I do post to facebook occasionally if I come across something to share. =)

►Please accept my apology for any broken links or videos that do not work. I am always disappointed when people take down their videos from YouTube. It makes it hard to find just the right replacement. And because the videos were posted years ago, I usually have no recollection of what the video was about.
I kept thinking I would have time after my kids graduated, but life has filled up my free time with new responsibilities. =)

►Please do not email, asking me to post your website link, or to review something to put on my site. Any resources posted on this site are things I had found on my own during my regular searching for material I needed at the time, and liked it well enough to post here. There have never been any affiliates on my site, and as it is no longer active, would not be worthwhile at this point. ;)
Thank you!

### Natural #'s, Whole #'s, Integers, Rational, & Irrational #'s

Natural Numbers vs. Whole Numbers at Virtual Nerd
►If that video helped you, here are more videos from Virtual Nerd about kinds of numbers.

YayMath.org

Algebra - Properties of Real Numbers from Yay Math on Vimeo.

Other examples:
►6/3 = 2, so this fraction is a natural number.  It is also a whole number, an integer, and a rational number.
►√4 = 2, so this is a natural number, a whole number, an integer, and a rational number.
Any number that can be written as a fraction is a rational number.  2 can be written as 2/1.
►√-1 is irrational, because the number inside the square root has been squared; multiplied by itself.
Such as √16 = 4.  16 is a square of 4.  So 4 is the square root.
BUT what would be the square root of √-16?  There is no answer, so this is irrational.