We will study about the “**Arithmetical Number Series**” in the reasoning section of the **IBPS** bank exam and others. In this portion, question will be numerical, alphabetical and alphanumeric. These questions have some tricks and tips for solving them. Applicant must check that how to solve questions and with an explanation. Candidate must have downloaded these notes in **PDF** format.

Contents

### What is arithmetical number series

In this series, there are missing one, wrong one and fill in the banks questions in numerical form and alphanumerical form.

Number series is a form of numbers in a certain sequence, where some numbers are mistakenly given into the series of numbers and some number is missing in that series, we need to observe first and then find the accurate number to that series of numbers.

Following the note of arithmetical number series tricks and arithmetical number series questions and tricks that helps in qualifying the IBPS Clerk and IBPS PO thus getting a good score.

### Types of number series

There are some format of series:-

- Perfect squares.
- Perfect cubes.
- AP(Arithmetic progression).
- GP(geometric Progression).

### AP(Arithmetic progression).

- where nth terms of sequences(
^{a}_{n}),^{a}_{1 }is first term, d is the common difference.

### GP(Geometric Progression).

This type of series are based on ascending or descending order of numbers and each successive number is obtain by multiplying or dividing the previous number with a fixed number.

where r is common ratio.

### Questions & Answers

Question 1: Look at this series: 2, 1, (1/2), (1/4), ... What number should come next?

Solution:

This is a simple division series; each number is one-half of the previous number.

In other terms to say, the number is divided by 2 successively to get the next result.

4/2 = 2

2/2 = 1

1/2 = 1/2

(1/2)/2 = 1/4

(1/4)/2 = 1/8 and so on.

Question 2: Look at this series: 22, 21, 23, 22, 24, 23, ... What number should come next?

Solution:

In this simple alternating subtraction and addition series; 1 is subtracted, then 2 is added, and so on.

Question 3: Look at this series: 7, 10, 8, 11, 9, 12... What number should come next?

Solution:

This is a simple alternating addition and subtraction series. In the first pattern, 3 is added; in the second, 2 is subtracted.

Question 4: Find out the wrong number in the series: 3, 8, 15, 24,34,48,63.

Solution:

The difference between consecutive terms is respectively 5, 7, 9, 11 and 13.So, 34 is a wrong number.

Question 5: Complete the series: 2, 5, 9, 19, 37…

Solution:

Second number is one more than twice the first; third number is one less than twice than the second; fourth number is one more than twice the third; fifth number is one less than the fourth.Therfore, the sixth number is one more than twice the fifth.

So, the missing number is 75.

Question 6: Find out the wrong one in the series 7, 8,18,57,228,1165,6996.

Solution:

Let the given numbers be A, B, C, D, E, F, G Then,

A,A*1,B*2+2,C*3+3,D*4+4,E*5+5,F*6+6 are the required numbers.So,228 is wrong numbers.

Question 7: Look at this series: F2, __, D8, C16, B32, ... What number should fill the blank?

Solution:

The letters decrease by 1; the numbers are multiplied by 2.

Question 8: Look at this series: VI, 10, V, 11, __, 12, III, ... What number should fill the blank?

Solution:

This is an alternating addition and subtraction series. Roman numbers alternate with Arabic numbers. In the Roman numeral pattern, each number decreases by 1. In the Arabic numeral pattern, each number increases by 1.

Question 9: Look at this series: J14, L16, __, P20, R22, ... What number should fill the

blank?

Solution:

In this series, the letters progress by 2, and the numbers increase by 2.

Question 10: 589245773, 89245773, 8924577, 924577, ?

.

Solution:

The pattern is The digits are removed one by one from the beginning and the end in order alternately, So to obtain the subsequent terms of the missing series is = 92457.

Here this article is related to :-

- number series notes
- number series quiz
- number series questions for ibps clerk
- number series questions and answers for bank exams