## How to Solve Number Series Tutorials

The “number series” tutorials of PH Civil Service review contains tutorials on methods and strategies used in solving number series problems. As I have mentioned in the teaser of this tutorials, the term “series” is technically wrong: what you are solving are really sequences. Although they maybe similar to many of you, to mathematics majors, they are very different.  In mathematics, series means sequence of sums. I will not go into details about this since this is irrelevant for the review. In this series of tutorials, mathematically, we will use the term “series” and “sequence” interchangeably.

1.) A Teaser on Answering Number Series Questions discusses a brief introduction to number sequence.

2.) How to Solve Number Series Problems Part 1 discusses simple integer, letter, and fraction sequence.  Continue Reading

## How to Solve Civil Service Exam Number Series Problems 1

First of all let me clarify that what you are solving in the Civil Service Examination are number sequences (or letter sequences) and not a number series. A series has a different meaning in mathematics.

Before proceeding with the discussion below, first, try to find the next term in the following sequences.

1. 4, 7, 10, 13, ___

2.  17, 11, 5, -1,  ___

3. C, F, I, L, ___

4. $\frac{1}{3}$, $\frac{5}{6}$, $\frac{4}{3}$, $\frac{11}{6}$.

Solution and Explanation

Numbers 1 and 2 are the easiest type of sequence to solve. This is because they are integers and you just add (or subtract) a constant number to each term to get the next term.  In solving this type of sequence, you can see this pattern by subtracting adjacent terms (13 – 10 = 3, 10 – 7 = 3, 7- 4 = 3) to see if the difference is constant. If it is, then you will know that you will just have to add the same number to get the next term. Therefore, the next term to the first sequence is 13 + 3 = 16. Continue Reading