Ch.9 :- Logical Alphabets Number And Time Sequence Test :- Introduction & Formula


1. Alphabets

There are a varied types of logical reasoning question that are based on the alphabet. Below, we discuss four prominent types of question asked in competitive examinations.

Type 1

Ex. 1: Arrange the following words in the alphabetical order and choose the word that comes exactly in the middle.
(a) Prominent
(b) Prohibition
(c) Programme
(d) Protracted
(e) Prolong

Sol.: If we arrange all the five words in the order which they occupy in dictionary, we get their order of positions as – Programme, Prohibition, Prolong, Prominent,Protracted. We find that the word Prolong comes in the middle. Hence, the correct answer is (e)

Ex.2 : Which of the following words will come at second position if all the words are arranged alphabetically?
(a) Arrangement
(b) Arrest
(c) Arrears
(d) Arrival
(e) Arrogant.

Sol.: In this question we observe that initial letters Arr are common to all the words. In this way word’Arrangement’ comes at the first position and word ‘Arrears’ at the second position. Hence, the correct answer is (c).

Type 2

Type 2

✦Directions : Examples (3-4)are based on the following letters of English alphabet. Study the pattern and then answer these questions.
A B C D E F G H I J K L M N 0 P Q R S T U V W X Y Z

Ex. 3 :If first half of the above alphabets is written in the reverse order, which letter would be 3rd to the right of 10th letter from the left ?
(a) F
(b) H
(c) B
(d) A

Sol.: If we reverse the first half of the alphabets, we shall have first letter of alphabet starting from left as M. Counting 10th from left we get letter D and from 3rd right of D we get letter’A. So, the correct answer is (d).

Ex. 4 :Which letter is exactly in the middle of the 20th letter from the right and 11th letter from left ?
(a) I
(b) J
(c) H
(d) 0

Sol.: We have 11th letter from left as K and 20th from right as G. And there are three letters between G and K. So I is exactly between G and K. So, the correct answer is (a).

Type 3

Type 3

Ex. 5 :How many sets of two letters have as many letters between them as in the alphabetical order in the word ‘ARISTOCRAT’ ?
(a) 1
(b) 2
(c) 3
(d) 4
(e) None.

Sol.: Pair ‘ST’ has not any letter in the word ‘ARISTOCRAT’ as well as in alphabetical order. Likewise, pairs ‘CA’ and ‘RT’ have one letter between them in the word as well as in the alphabetical order. Therefore, we have three such pairs of letters. Hence, the correct answer is (c).

Type 4

Type 4

Ex. 6 :If it is possible to form a word with 1st,4th, 7th and 11th letters of the word ‘SUPERFLUOUS’, write the first letter of that word. Otherwise, X is the answer.
(a) S
(b) L
(c) O
(d) E
(e) X

Sol.: ‘LESS’ is the word which is formed by using 1st, 4th, 7th and 11th letters of the word ‘SUPERFLUOUS’. First letter of this word is L. Hence, the correct answer is (b).

2. Number Ranking

Type 1

Ex. 7 :In a class of students, Ravi occupies 5th position from the top and 25th from the bottom in a test. How many students are there in the class?
(a) 30
(b) 28
(c) 29
(d) 25
(e) None of these

Sol.: Total number of students in the class = Position of  Ravi  from top + Position of  Ravi  from. I bottom = I) =
Using the above rule we get total number of students = (25 + 5)  – 1 = 29. Hence, the correct answer is (c).

Ex.8 :How many 3 s are immediately preceded by 9 but not immediately followed by 5 in the following number series?
9 3 4 5 9 3 5 9 3 6 4 3 9 3 3 5 3 9 5 3 9 3 7 5 7 5 9 3 9 5
(a) 4
(b) 3
(c) 5
(d) 3
(e) None of these.

Sol.: 9 3 4 5 9 3 5 9 3 6 4 3 9 3 3 5 3 9 5 3 9 3 7 5 7 5 9 3 9 5

All 3 s which are immediately preceded by 9 but not immediately followed by 5 have been assigned the sign 3.The total no. of such 3 s is 5. So, the correct answer is (c).