# How To Solve Coding And Number Series Quickly

## Concept of Coding And Number Series:-

Letter-Number Coding is a mark scoring section of the reasoning questions. In competitive examinations **reasoning** contain a most important part. If you achieve good marks in reasoning you will get a good score and rank in competitive examinations.

The best way to understand Number series coding is by going through its solved questions. Reasoning is all about more and more practice. Here are a few solved Questions to help you in a better way.

## Methods to Solve Coding And Number Series Quickly:-

**Types of Number Series:**

**1)Perfect Square Series:**

**Example**– 324 = 18^{2} , 361 = 19^{2}, 400 = 20^{2}, 441 = 21^{2}, 484 = 22^{2}

**2)Perfect Cube Series:**

**Example**– 8^{3}=512, 9^{3}=729, 10^{3}=1000, 11^{3}=1331

**3)Geometric Series:**

**Example- **4\times 5=20,20 \times 5=100,100\times 5=500,500 \times 5=2500

**4)Arithmetic Series:**

**Example- **4,8,12,16,20,24,28

The common difference is constant that is 4.

**5)Two Stage type Series:**

**Example-**1, 3, 6, 10, 15…

3 – 1 = 2, 6 – 3 = 3, 10 – 6 = 4, 15 – 10 = 5….

Now, we get an arithmetic sequence 2, 3, 4, 5

**6)Mixed Series:**

**Example-**10, 22, 46, 94, 190,?

10\times2 = 20 +2 = 22,22 \times 2 = 44 + 2 = 46,46 \times 2 = 92 + 2 = 94,94 \times 2 = 188 + 2 = 190,190 \times 2 = 380 + 2 = 382.

So the missing number is 382.

**7)Arithmetic-Geometric Series:**

**Example- **1, 4, 8, 11, 22, 25, ?

Series Type +3 , \times2 ({\text{i.e Arithmetic and Geometric Mixing}})(e.g: 1+3=4;4\times 2=8)

**8)Twin/Alternate series:**

**Example-** 3, 4, 8, 10, 13, 16 ? ?

Sol: As we can see, there are two series formed

Series 1 : 3, 8, 13 with a common difference of 5

Series 2: 4, 10, 16 with a common difference of 6

So, the next two terms of the series should be 18 & 22 respectively.

**Few Examples of Coding:**

**Question 1:**

If in a certain language A is coded as 1, B is coded as 2, and so on, how is B I D D I C coded in that code?

**Option:**

A) 294493

B) 284563

C) 375582

D) 394492

**Answer:** A

**Explanation:**

As given the letters are coded as:

A B C D E F G H I

1 2 3 4 5 6 7 8 9

So, in B I D D I C, B is coded as 2, I as 9, D as 4, and C as 3. Thus, B I D D I C is coded as 294493.

**Question 2:**

If D is coded as 4 and C O V E R is coded as 63, then BASIS will be coded as?

**Option:**

A) 54

B) 55

C) 49

D) 50

**Answer:** D

**Explanation:**

It is clear that the code is arrange in this mannerA = 1. B = 2, C = 3 … so on

so that C O V E R is coded as [C+O+V+E+R]

⇒ 3 + 15 + 22 + 5 + 18 = 63.

Now B A S I S is coded as [ B+A+S+I+S]

⇒2 + 1 + 19 + 9 + 19 = 50.

**Question 3:**

bcd’ is coded as ‘def’ then ‘True’ is coded as……….

**Options:**

A) Hynx

B) Vrwx

C) Zbyw

D) Vtwg

**Answer:** D

**Explanation:**

b – d (+2)

c – e (+2)

d – f (+2)

+2 letters are considered in this code.

True – Vtwg

**Question 4:**

In a certain code ‘MONARCHY’ is written as ‘NPOBSDIZ’. How will ‘STANDARD’ be written as in that code?

**Options:**

A) TUBOEBSE

B) TVBSHBNW

C) WEHJSOLX

D) GHWQMKLJ

**Answer:** A

**Explanation:**

Each letter of MONARCHY is replaced by the next letter as per the alphabet

M+ 1 = N

O+ 1 = P

N+ 1 = O

A+ 1 = B

R+ 1 = S

C + 1= D

H+ 1 = I

Y+ 1 = Z

Similarly, STANDARD is written as TUBOEBSE