1. Fill in the following numbers in words.

a. 34.7  __________.

b. 20.2  __________. 

c. 0.05  __________.

d. 10.12 _________.

Answer

a. Thirty four point seven

b. Twenty point two

c. Zero point zero five

d. Ten point one two

2. Match the meaning of each prefix.

a.  Deca               (i)   One tenth

b.  Kilo                 (ii)  One thousandth

c.  Milli                (iii)  One thousand

d.  Deci               (iv)  One ten

Answer

a. (iv)   b. (iii)  c. (ii)  d. (i)

3. State whether true or false.

1. The smallest 3 - place decimal is 0.001 .

2. 10 metres is equal to 1 decametre.

3. 100 centimetre is equal to 1 kilometre.

Answer

1. True

2. True

3. False

4. Write each as decimals.

5. Write each as a fraction or a mixed numeral.

     a) 0.8         b) 6.7      c) 31.2

6. Write as mixed numeral.

     a) 35.1       b) 21. 2

7. Write decimal numeral for each of the following:

    a) Nine tenths      b) six and one tenth      c) seven hundred ths.     d) Four thousand ths.

a) Nine tenths           =  9/10  = 0.9

b) six and one tenth   = 6 ¹/₁₀ = 6.1

c) Seven hundred ths = ⁷/₁₀₀  = 0.07

d) Four thousandths   = ⁴/₁₀₀₀  = 0.004

8. Write each of the following in words.

    a) 0.7    b) 0.39    c) 3.69

a) 0.7  = Seven tenths

b) 0.39 = Thirty nine hundredths

c) 3.69  = Three and sixty nine hundredths.

9. Expand each decimal numeral.

     a) 5.623     b) 463 . 70      c) 1.125

a) 5.623    =  5 + 0.6  + 0.02 + 0 . 003

b) 463.70  =  400 + 60 + 3 + 0 .7 + 0

c) 1.125    =  1 + 0.1 + 0. 02 + 0. 005.

10. Write the value of 6 in the following.

       a) 0.36     b) 1.62    c) 6.57

a) 6 hundredths

b) 6 tenths

c) 6 ones

11. Write the smallest 3 - place decimal.

The smallest 3 - place decimal is 0.001     

12. Change the following to tenths and then write as decimals.

13. Change the following to hundredth and then write as decimals.

       a. ²/₅       b. ¹/₂₅      c. ⁷/₂₀   

14. Change each of the following to a fraction in simplest form.

      a) 0.4     b) 0.75     c) 0.20

15.  Find the value of :

      a) 0.5 + 0.4     b) 0.81  + 0.17

16. Find the value of :

     a) 12.05 + 36 . 73      b) 75. 68 + 86 . 87

17. Find the value of 3 - 0.3 - 0.03 - 0.003.

∴ 3 - 0.3 - 0.03  - 0.003  =  2. 667.

18. Substract the difference of 45. 593 and 43. 276 from their sums.

∴   Required answer   = 86 . 552.

19. Add the difference of 145. 426 and 76 . 75 to their sum.

20. Express in metres.

       a) 7.3 km       b) 3.4 cm

a) 7.3 km =  7.3 × 1000 m

               =   7300 m

                 =  0.34 m

21. Express in Kilometres.

       a) 478 m     b) 820 mm

                           = 0. 478 km

22. Rearrange the decimal numbers 5. 893,  5 . 983,  5. 909, 5.913 in order of size, starting with the largest.

First write the largest whole number, then the largest tenths, then the hundredths and so on.

Hence the answer is 5.983, 5.913, 5.909, 5.893.