Adding and Subtracting Decimals

Decimals are also included in the Civil Service Commission’s Number and Reasoning Test. In this exercise, we’ll focus on adding and subtracting them properly. Learning this basic computation will help you have an easier time with these type of questions. Moreover, the process is quite easy as all you have to do is just line up the given numbers by their decimal point and then add or subtract them. Take a look at the examples below;

12.3 + 5.63 + 28.9 = ?

8.03 + 19.50 + .704 = ?

84. 369 – 53.248 = ?

243.672 – 38.089 = ?

The solutions are:

 

If a number doesn’t have a decimal point, just put one and align it to the other numbers. In addition, you could also put zeros if you want so you won’t be confused. You’ll usually use those imaginary decimal point and zeros when subtracting decimals. Again, check out an example below;

95 – 44.579 = ?

The solution is:

 

This process is not as time consuming as the CSC Exam Number Sequence and Reasoning reviewer, therefore, more exercises are presented for you to do. Don’t forget to write down your answers in a sheet of paper or notebook.

 

CSC Exam Reviewer: Addition of Decimals

Here are some basic addition of decimals with a bit of a twist to jump-start your number reasoning skills.

1. 0.2 + 0.38 = ____

2. 0.9 + 0.8 = ____

3. 0.8 + 1.93 = ____

4. 0.6 + 1.2 = ____

5. 0.194 + 0.658 = ____

6. 1.8 + 1.6 = ____

7. 1.9 + 1.30 = ____

8. 0.975 + 0.169 = ____

9. 19.92 + 12.28 = ____

10. 15.35 + 17.86 = ?

11. ____ + 6.5 = 12.4

12. ____ + 5.1 = 13.8

13. 5.9 + ____ = 12.7

14. ____ + 7.4 = 10.1

15. 6.4 + ____ = 7.2

16. 9.6 + ____ = 16.6

17. 1.7 + ____ = 9.8

18. ____ + 28.2 = 46.2

19. ____ + 13.5 = 53.4

20. 17.4 + ____ = 36.9

CSC Exam Reviewer: Subtraction of Decimals

Just like addition, these decimal subtractions offer a bit of a challenge.

1. 9.0 – 3.5 = ___

1. 3.5      b. 4.5      c. 5.5      d. 6.5

2. 7.4 – 5.3 = ___

1. 2.1      b. 2.3      c. 2.5      d. 2.7

3. 3.6 – 1.7 = ___

1. 1.7      b. 1.5      c. 1.8      d. 1.9

4. 4.45 – 0.4 = ___

1. 4.41      b. 4.05     c. 4.39      d. 4.04

5. 6.8 – 0.71 = ___

1. 6.90      b. 6.59      c. 6.09      d. 6.95

6. 6.1 – 1.24 = ___

1. 3.96      b. 4.46      c. 4.86      d. 5.26

7. 7.7 – 2.5 = ___

1. 2.5      b. 5.2      c. 2.2      d. 5.5

8. 33.24 – 17.83 = ___

1. 18.41      b. 17.14      c. 16.14      d. 15.41

9. 42.95 – 21.39 = ___

1. 21.56      b. 22.36      c. 22.96      d. 23.06

10. 97.8 – 61.4 = ___

1. 35.2      b. 36.4      c. 38.6      d. 40.2

11. ___ – 1.9 = 0.1

1. 3      b. 2.6      c. 2.1      d. 2

12. ___ – 1.2 = 2.4

1. 1.1      b. 1.2      c. 1.3      d. 1.4

13. 3 – ___ = 1.2

1. 1.2      b. 1.4      c. 1.6      d. 1.8

14. ___ – 0.4 = 0.3

1. 0.7      b. 0.6       c. 0.5       d. 0.4

15. 3.8 – ___ = 2

1. 1.6      b. 0.17      c. 1.8       d. 0.19

16. ___ – 1.7 = 3.4

1. 1.7      b. 1.77      c. 1.17      d. 1.07

17. 3 – ___ = 2.6

1. 0.40      b. 0.60      c. 0.80      d. 1

18. 76.53 – ___ = 8.71

1. 65.83      b. 67.82         c. 69.91      d. 71.93

19. ___ – 34.52 = 2.7

1. 35.26      b. 36.24      c. 37.22      38.20

20. 62.6 – ___ = 12.9

1. 46.4      b. 47.5      c. 48.6      d. 49.7

Once you are through with the exercises above, you may click any buttons below to reveal the answers and to see how many correct questions you’ve answered correctly.

If you have a total of 36 correct answers, you did excellent. If on the other hand you scored less than that, try it again from the beginning so you could get used to adding and subtracting decimals.