Study Notes: Number Series for Bank PO

Number Series  Study Notes

Candidates considers Quantitative Aptitude as one of the tough section among other section of IBPS PO Exam. While Quant section is scoring, the questions are tricky as well. Students needs to learn lots of approaches to ace marks in quant section of ibps po exam.

Bankersadda have come up with a new inititative “KAR IBPS PO FATEH” ! Under this, we have shared the Study Plan for ibps po exam has already been published with you, now we have come up with the study notes on Quantitative aptitude, Reasoning and English Section. In the series of study notes for ibps po exam, today, we are discussing some different approaches to handle Number Series for ibps po exam. This study note will surely help you to score better in quant section of the exam.

Number Series: Study Notes for IBPS PO Exam  

Nowadays, Number Series plays an important role in prelims as well as mains exams of banking and other sector exams. It is the part of almost every banking exams, where quantitative aptitude is an ineluctable hitch. In exams like IBPS PO, SBI PO, IBPS RRB, etc., Question-related to number series is being asked for 5 to 6 marks in prelims and also 5 to 6 marks in mains exam. There are two types of number series namely-wrong number series, missing number series. The level of difficulty may vary in each exam. It becomes necessary to be very handy on this topic to ace in this part of the quantitative aptitude section.

→ Basically, in Banking PO level exams, three types of series are asked

(i) Missing number series
(ii) Wrong number series
(iii) Double pattern series or multiple pattern series
Missing Number Series



Missing number series is a particular series in which a specific pattern is being followed by the numbers given in the series and there is one number missing in the series and it is to be found by following the given pattern. 

                                        
Different types of number series are given as follow:-

(1) Single-stage difference: – In single-stage difference, there is a continuous difference followed in the complete series
Ex-

→ Here, pattern followed is + 25, +50, +75, +100, +125
Ex- 
Approach to solve such series in a faster way:- 
First of all, you should be able to find out that this series is a ‘Difference Pattern’ series. So, in this type of series value do not get increased or decreased by a very large value.
In such series, to solve it faster you should check the difference followed by 1st half number series only or only second half of number series, and then you will get the exact pattern followed, thus you can save your time

For ex-
By observing 1st half of the series, we will be getting the exact order and pattern of the series
(2) Double Stage difference:- In this type of series also value do not get increased or decreased by a very large value.
In double stage difference, the difference followed is in some continuous pattern and after that, another pattern of difference is created with respect to the initial difference created.
Ex-
→ In this series, the difference obtained in 1st stage is +12, +20, +30, +42, +56 and with the help of difference obtained in first stage, the 2nd stage difference is +8, +10, +12, +14
Approach to solve faster

To solve such series in a faster way is solving 1st four number we will get the pattern of the number series.
(3) The difference of Square or cube of numbers based Series:- In such number series, the difference created is the difference of squares of natural numbers
Ex-
→ Here, the difference created is squares of consecutive number from 4 to 8
Ex-
→ In square number series, there is also a new pattern followed in the exams
Ex 
→ Here, the difference created is the square of the number and addition of that particular number
Ex-
→ In this series, the difference created is the difference of cubes from 5 to 9
→ In cubic series, there is also a new pattern being followed nowadays. In such a pattern, the cubes of a number and also the particular number is added
Ex 
In these types of series as soon as we find the pattern, we should find the missing value directly rather than calculating each value of the series
(4) Multiplication type series: – In such type of series, each term of the value is increased by a very large value
 Ex 
→ In such a series, the pattern followed is ×3, ×4, ×5, ×6
Approach to solve faster:- 

To solve such series in a faster way, try to solve the given series by dividing it into 2 half. Then solve 1st half and then you will get the exact pattern and as soon as we find the pattern, we should find the missing value directly rather than calculating each value of the series
In multiplication series, there is also a new pattern being followed which is given as follow-
Ex 
→ In given series, the pattern followed is multiplication by a number and adding that particular number
Approach to solve faster:- In such a series, you can save your time and calculate it faster by trying to check the pattern by taking the first three to four numbers.

(5) Division type series:-
In division type series, a particular number is being divided by a number and such pattern is being followed. In such series, the next number in the series is decreased highly from the previous number
Ex –
(6)Mix Type Series:-
In such type of series, the pattern followed is based on more than one type/method. Such type of series is nowadays in trending in exams especially in mains exam
Ex –
→ In such type of series, a pattern followed is ×6+5, ×5+4, ×4+3, ×3+2, ×2+1
Ex –
(7) Prime number series:- 
In prime no. series, the difference created in the series is the difference of consecutive prime numbers
Ex –
→ Here, in this series the difference created is the difference of prime no. (consecutive) i.e. 23, 29, 31, 37, 41
Ex –
In this series, the difference created is the subtraction of prime numbers i.e. 59, 53, 47, 43, 41
Wrong Number Series

In wrong number series, a particular series is given which follows some specific pattern, from which one of the numbers is wrong such series is known as wrong number series and following the given pattern you have to identify the wrong numbers. 
→ In the wrong number series, there are different types the same as mentioned above in the missing number series
(1) Single-stage difference:-

In single-stage difference, there is a continuous difference followed in the complete series and among them, there is one wrong number in the whole series.
Ex
(2) Double Stage difference:-
In these types of series also value do not get increased or decreased by a very large value
In Double stage difference wrong number series, there is a specific pattern followed and among them there is a wrong number among the given series.
Ex

(3) The difference between Square or cube of numbers based Series:-
In these types of wrong number series, there is a specific pattern followed whose difference is squares and cubes of the number and among them, there is a wrong number among them in the given series which does not follow the given pattern.
Ex
(4) Multiplication type series:-
In these types of wrong number series, the difference obtained is the multiplication of a specified pattern and among them, there is a wrong number among the given series 
Ex
(5) Division type series:-
In these types of wrong number series, the difference obtained is the division of a specified pattern and among them, there is one wrong number among the given series.
Ex
(6)Mix Type Series:-
In mix type wrong number series, the difference obtained is followed by more than two patterns and among them, a given number is wrong which does not follow the specified pattern
Ex
In multiple pattern series, there may be two or more than two series are given. Based on the pattern of first, second or third series has to be obtained This type of series is mainly asked in mains exams of banking exams. Multiple pattern series is the most difficult type of number series but with practice and right approach it can be cracked easily.
Ex     
1,    3,    9,    31,    129,    651                                                                                                                        
2,  _,  __,    __,      ____,        ?
In this kind of series, a particular type of series is given which follows a specific pattern and according to which another pattern is obtained following the same pattern of the above series.  Therefore, this kind of series is a little bit tricky to solve.
Ex
A series is given below followed by another series which follows the same pattern as of first series. Find the the value of ‘m’
113, 170, 232, 303, 399, 556, 838. 
93, __, __, __, __, __, m. 
Sol. 

By observing the pattern of the first series we can find the value of m
Similar Pattern will be followed in the second series also so,

 m= 818

Approach to solve faster

Once we find the pattern of the first series tries to not calculate each value of the second series. Just jump to the value asked and find the value of it. As an example, from the first series, we know that the same difference will also be there in the second series

So students prepare well for the upcoming banking examination. Do practice with the Quantitative aptitude quiz provided on bankersadda. Practice from different types of questions will help you ace in the banking examination. Do not leave any loophole. Revise all the study notes of quant to be on the top of the edge.