Real Numbers Worksheet (Page 4 of 4) in pdf

Real Numbers Worksheet Page 4

MAP

Mathematics Achievement Program

SFSU – High School Collaborative

Example 7:

Approximate the irrational number 17 to three decimal places.

We use a calculator to find an approximation of

17 :

17 ≈

. 4

123105626

We round the decimal to three places and obtain:

17 ≈

. 4

123

(

)

17 ≠

≠

Notice that

. 4

123

because

. 4

123

999129

________________________________________________________________________

30a. Using your calculator, find

2 and write this number in your notebook.

x key on your calculator) to verify that its

b. Now square the number (press the

square is 2.

c. Clear the calculator, and then enter the number written in your notebook from

part a above. Square this number. What answer does the calculator give?

d. Compare the two answers from parts b) and c) above. What has occurred?

31a. Approximate

17 to six decimal places.

17 =

b. Does

. 4

123105626

? Explain.

32. Can the infinite decimal 0.010010001000010000010000001… be written as a

fraction or is it an irrational number? Explain.

Real Numbers Worksheet Page 4