Problem Set 1

EQ: How and why are numbers classified?

1. Take a look at this list of animals and organize them into groups. Be prepared to explain HOW you grouped them.

2. Now let’s look at classifying numbers. Look at how real numbers are classified below. Now, look at some examples of each classification. What do you notice? Write at least 3 observations.

Natural: 1, 2, 3….Whole: 0, 1, 2, 3, …..Integers: -2, -1, 0, 1, 2, …Rational: -5.78, 0.22, ½, 500, …Irrational: √2 , π , …

I notice ____________________________________________________________________

I also notice _______________________________________________________________

Finally, I notice ___________________________________________________________

3. The number 1/3 is a real, rational number. The number is a real, π irrational number. Put both those numbers in your calculator. Write down what you notice.

You’ll notice that your calculator has a F>D button and D>F button. The “F” stands for fraction and the “D” stands for decimal. Try using that button with 1/3 (F>D) and (D>F). What do you notice?π

Now, come up with a thoughtful definition for a rational and an irrational number. (You’ll need two different definitions)

4. Carol telephoned Santos about a homework problem. Santos said, “Four plus three times two is 14, isn’t it?” Carol replied, “No, it’s 10.” Did someone make a mistake? Where did these two answers come from?