PARTS OF NATURAL NUMBERS

PROBLEMS

Do the problem yourself first!

11.   a)  Which numbers are the first five multiples of 6?

6, 12, 18, 24, 30.

11.   b)  6 is which part of each one of those (except 6)?

6 is half of 12.

6 is the third part of 18.

6 is the fourth part of 24.

6 is the fifth part of 30.

12.  Complete the following with the word multiple or part.

12.  a)  A larger number is a multiple of a smaller number.

12.  b)  A smaller number is a part of a larger number.

12.  c)  "3 is the fifth part of 15" means, 15 is the fifth multiple of 3.

12.  d)  Since 12 is the third multiple of 4, we say that 4 is the third
12. d)    part of 12.

12.  e)  40 is eight times 5, therefore 5 is called the eighth part of 40.

12.  f)  Every number is a certain part of each of its multiples.

12.  g)  A number is divisible by 9, is the same as saying that the number
12. g)   is a multiple of 9.

12.  h)  Each divisor of a number (except the number itself) is a certain
12. h)  part  of the number.

13.  Spell the ordinal name of each of the following:

 4  Fourth 5  Fifth 8  Eighth 9  Ninth 12  Twelfth 19  Nineteenth 20  Twentieth 21  Twenty-first 30  Thirtieth 40  Fortieth 100  Hundredth 101  Hundred first

14.  a)  Which numbers are the divisors of 6?  1, 2, 3, 6.

14.  b)  Each divisor (except 6) is which part of 6?

1 is the sixth part of 6.

2 is the third part of 6.

3 is half of 6.

15.  a)  Find all the divisors of 18 in pairs.

1 and 18

2 and 9

3 and 6

15.  b)  Each divisor (except 18) is which part of 18?

1 is  the eighteenth part of 18.

2 and 9

2 is the ninth part of 18.  9 is half of 18.

3 and 6

3 is the sixth part of 18.  6 is the third part of 18.

16.  a)  Find all the divisors of 24 in pairs.

1 and 24

2 and 12

3 and 8

4 and 6

15.  b)  Each divisor (except 24) is which part of 24?

1 is  the twenty-fourth part of 24.

2 and 12

2 is the twelfth part of 24.  12 is half of 24.

3 and 8

3 is the eighth part of 24.  8 is the third part of 24.

4 and 6

4 is the sixth part of 24.  6 is the fourth part of of 24.

17.   Write the first five numbers that have

17.  a)  a third part.  3, 6, 9, 12, 15.

17.  b)  a fourth part.  4, 8, 12, 16, 20.

17.  c)  a fifth part.  5, 10, 15, 20, 25.

18.   1 is a part of every natural number (except itself).  Which part is it of

2  Half.     3  Third.     4  Fourth.     10  Tenth.

79  Seventy-ninth.     1000  Thousandth.

19.   How much is each of the following?

 An eighth of 8?  1 A tenth of 10?  1 A fifth of 5?  1 A sixth of 42?  7 An eighth of 24?  3 A fifth of 10?  2 A tenth of 40?  4 A fourth of 20?  5 A ninth of 9?  1 A third of 21?  7 A fifth of 40?  8 A seventh of 63?  9 An eighth of 72?  9 A fourth of 36?  9 A sixth of 6?  1

10.  Complete the following.

6 is the third part of 18.

6 is the fourth part of 24.

6 is half of 12.

10 is the fifth part of 50.

10 is the eighth part of 80.

3 is the seventh part of 21.

1 is the fourth part of 4.

1 is the sixth part of 6.

8 is the ninth part of 72.

11.  a)  7 is which part of 21?  The third.

11.  b)  6 is which part of 24?  The fourth.

11.  c)  9 is which part of 45?  The fifth.

11.  d)  8 is which part of 72?  The ninth.

11.  e)  1 is which part of 12?  The twelfth.

11.  f)  1 is which part of 100?  The hundredth.

11.  g)  10 is which part of 100?  The tenth.

12.  Same digits; powers of 10.

12.  a)  \$45 is which part of \$450?  The tenth.

12.  b)  \$4.50 is which part of \$450?  The hundredth.

12  c)  \$.45 is which part of \$450?  The thousandth.

13.  The parts of 100%.  Which part of 100% is

50%?  Half.     25%?  A fourth, or a quarter.    20%?  A fifth.

10%?  A tenth.      5%?  A twentieth.        1%?  A hundredth.

14.  Whichever part the percent is of 100%, the percent means that part.

14.  Compare the following.

14  a)  6 is half of 12.   6 is 50% of 12.

14.  b)  9 is a fourth of 36.   9 is 25% of 36.

14.  c)  7 is a fifth of 35.   7 is 20% of 35.

14.  d)  6 is a tenth of 60.   6 is 10% of 60.

14.  e)  \$3.45 is a hundredth of \$345.   \$3.45 is 1% of \$345.

15.  Into which parts could you divide 16 people?

Halves, fourths, eighths, and sixteenths.
Each part is the ordinal name of a divisor.

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