4th Class Science Reasoning and Aptitude Reasoning Aptitude

Reasoning Aptitude

Category : 4th Class

Reasoning and Aptitude

Introduction

Learning process is dependent on ones ability to think logically and reason quickly and effectively. So Reasoning and logic skills are an important part in our progress 55 these skills are very useful in our day to day life. In this chapter, we will learn various problems related to reasoning and aptitude.

Problems Based on Patterns

Pattern is a list of numbers or letters that follows a certain sequence or a certain rule. To find the missing term or next term in series to continue the given series, first we must have a rule. To solve them all, we have to do is figure out the pattern and come up with the next logical number or letter of the sequence.

Example:

The values of A and B in the given number pattern are:

(a) 4,125 (b) 1,125

(e) None of these

Answer (b)

Explanation: Here, pattern followed is:

and

Therefore, the value of A and B is 1,125

Ø Example:

Which number will replace the question mark (?) in the number pattern given below?

(a) 31 (b) 28

(e) 26

Answer (d)

Explanation: Here, rule followed is:

and

Therefore, the missing number is 29

Problems Based on Coding and Decoding

Coding is a method of expressing something in secret way and decoding is a process to understand a code language.

Word Coding

In word coding, some particular words are assigned certain substitute names, a question is asked that is to be answered in the substituted code language.

Example:

If 'India' is called 'Germany' 'Germany' is called 'Japan', and 'Japan' is called 'Britain', then 'Tokyo' is the capital of which country?

(a) India (b) Germany

(e) None of these

Answer (d)

Explanation: 'Tokyo' is the capital of 'Japan' and 'Japan' is called 'Britain’

Letter Coding

In letter coding, letters are used in forward or backward or in both directions for making some code language. In some questions, letters of a word are directly replaced the other letters. For example:

Here P, I, C, T, U, R and E are replaced by F, L, X, Z, D, E and M, respectively. In this code, we can write the word PRICE as FELXM.

Example:

In a certain language, if the code for PEACOCK is KCOCAEP, then what is the code for ELEPHANT in that language?

(a) TAPLNHE (b) TANHPLEE

(e) None of these

Answer (c)

Explanation: Letters of the word PEACOCK are written in reverse order as a code. Therefore, the code for ELEPHANT is TNAHPELE.

Example:

If GOING is coded as IQKPI, then how is the word ALONG coded in that language?

(a) CNQPI (b) BMPOH

(e) None of these

Answer (a)

Explanation: Here,

Number Coding

In number coding, numerals are assigned to words.

Example:

If FRANCE is coded as 539624 and EGYPT is coded as 47810, then how will CENTRE be coded?

(a) 420643 (b) 246034

(e) None of these

Answer (b)

Explanation:

F	R	A	N	C	E	E	G	Y	P	T
5	3	9	6	2	4	4	7	8	1	0

Therefore, CENTER will be coded as '246304'

Problems Based on Direction Sense Test

The concept behind the directions is same that we use in our daily life. To solve n direction sense test first we need to make a sketch of the data provided.

Four main Directions are: North (N), South (S), East (e), West (W).

Four Cardinal Directions are: North-East (N-E), North West (N-W), South-East (S-E), South-West (S-W).

Direction Facts:

At the time of sunset, the shadow of an object (or a man facing East) the East.
At the time of sunrise, the shadow of an object is always in the West.
If a man stands facing the North at the time of sunrise, his shadow will be
his left and at the time of sunset, it will be towards his right,
At 12:00 noon, the rays of the sun are vertically downward, hence there will be no shadow.

Clockwise and Anticlockwise Turn

If you move in direction which is same as the moving direction of a clock hands, your movement is called clockwise turn. Clock wise Turn Anticlockwise Turn "you move in the opposite direction of the clockwise direction, your movement is railed anticlockwise turn.

Example:

Garima starts moving from a point P towards East. After walking some distance she turns her left. Now, her direction is definitely towards:

(a) South (b) North

(e) None of these

Answer (b)

Explanation: Here, we make sketch as follow:

Example:

Joseph is facing the stadium. He makes a — turn to the left. What will he be facing now?

(a) School (b) Railway Station

(e) None of these

Answer (a)

Explanation: In first turn, Joseph will face 'Home', in secondturn, he will face 'Railway Station" and in thirdturn or in a complete turn he will face "School?

Problems Based on Analogy

Simple meaning of analogy is similarity. But, in terms of reasoning, the mean analogy is logical similarity in two or more things. In problems based on Analog will usually be given one pair of images that are connected in a particular way and the first image of a second pair. We have to find the correct image to complete second pair in the same way as the first pair.

Ø Example:

Find the matching pair.

(a) (b)

(e) None of these

Answer (b)

Explanation: In first figure of left pair, middle figure becomes the outer figure, outer figure becomes inner figure and inner figure becomes middle figure. In both figures of left pair, outer figures and inner figures are shaded, while middle figure is unshaded.

Ø Example:

Find the missing pair.

(a) (b)

(e)

Answer (c)

Explanation: Here, pattern followed in left pair:

Therefore, pattern followed in right pair:

Problems Based on Figure Series

A figure series is a sequence of many elements made of figures. To solve these of questions, we observe shapes within shapes and patterns within patterns.

Ø Example:

What comes next?

(a) (b)

(e) None of these

Answer (c)

Explanation: Here, the square rotates one step anticlockwise in every next figure and one X is increasing in every next figure.

Hence, required figure is in option (c).

Problems Based on Geometrical Shapes

Geometrical shapes come from geometry which is the math of shapes made of point and lines. Some shapes are simple such as the triangle, square and circle other shapes are complex. While solving nonverbal reasoning based on geometrical shapes, following points are important:

Largest Perimeter: If the length of a figure does not change but width changes, then the figure having largest width have the largest perimeter.
Symmetrical Figure: If a line divides a figure into two identical parts, then the figure is symmetrical and the line is called Line of Symmetry.
Counting Geometrical Shapes: In order to count the geometrical shapes, we identify the shapes and solids by their names and images.
Net of a Cube: Net is a pattern that we can cut and fold to make a model of a solid shape. A net of a cube has 6 faces and when folded, it forms a box.

Ø Example:

How many horizontal lines are there in the given figure?

Explanation: Here, given figure is symmetrical about the dotted line.

Now, number of horizontal lines on the left of dotted line is 4.

Hence, total number of horizontal lines is 42 = 8

Ø Example:

Select the odd one out?

(a) (b)

(e)

Answer (d)

Explanation: Figure given in options (a), (b), (c) and (e) has exactly one line of symmetry. Figure given in option (d) has no line of symmetry.

Ø Example:

Which one of the following figures has a line of symmetry?

(a) (b)

Explanation:

Only the figure given in option (b) has a line of symmetry.

Problems Based on Mirror Images

In a plane mirror, if we lift our right hand, the image in the mirror shows our hand and if we lift our left hand, the image shows our right hand. Therefore, in a mirror image, the left part of an object becomes right part and the right part become left part.

Left Hand Side (LHSRight Hand Side (RHS)