6th Grade Math Textbook, Progress

Make and complete a table like the one below for the

numbers 1–20. Use the table for exercises 27–35.

27. Which numbers are
    prime numbers?


28. Which numbers are
    composite numbers?


29. Which numbers have
    exactly three factors?


30. Which number has
    only one factor?


31. Which numbers have
    six factors?


32. Which number is a factor 33. Which numbers have both 2
    of all of the numbers? and 3 as factors?


33. Which numbers have both 2 35. Which numbers have both 4
    and 5 as factors? and 8 as factors?

1

2

3

17

18

19

20

Number

?

?

Factors

1

1, 2

1, 3

?

?

Number of

Factors

1??????

Prime or

Composite

neither

prime

?

?

?

?

?

Six is called a perfect number because it is the sum of all

its factors, not including itself.

The factors of 6 are 1 , 2 , 3 , 6.

1 
 2 
 3  6

40. Find another perfect number. 41. Are any prime numbers also
    Extend the table above to help you. perfect numbers? Explain.


41. Use the internet or reference books to define these two types of numbers: (a)
    deficient numbers and (b) abundant numbers. Discuss your results with the class.


42. Why is the number 1 neither prime 37. Why is 2 the only even prime
    nor composite? number?


43. Rita’s locker number is a two-digit 39. Carl ran 4 km every day for 5 days.
    prime number. There are 25 lockers, Ken ran 3 km every day for 7 days.
    numbered 1–20, in Rita’s classroom. Was the total number of kilometers
    What are the possible numbers that both Carl and Ken ran prime or
    could be Rita’s locker number? composite? How do you know?

8206-2_180-181 1/12/06 3:30 PM Page 181