Type 1 Number Test

In these types of questions, a number, a set of numbers, series of digit is given and the candidate is asked to trace out digit following certain given conditions.

Example 1 How many 5s are there in the following number sequence which are immediately preceded by 7 and immediately followed by 6?

Terms : 7 5 5 9 4 5 7 6 4 5 9 8 7 5 6 7 6 4 3 2 5 6 7 8

(a) 1
(b) 2
(c) 3
(d) 4

Solution. (a) Here,7 5 5 9 4 5 7 6 4 5 9 8 7 5 6 7 6 4 3 2 5 6 7 8

Preceded by 7 and followed by 6 So, there is only one such 5.

Type 2 Ranking Test

In these types of questions, generally the ranks of a person both from the top and from the bottom are mentioned and the total number of persons is asked.

Example 2 : A class of boys stands in a single line. One boy is nineteenth in order from both the ends. How many boys are there in the class?

(a) 27
(b) 37
(c) 38
(d) 39

Solution. (b) Clearly, number of boys in the row = (18 + 18 + 1) = 37

The question can be solved by formula also, total number of boys in the row = 19 + 19 - 1 = 37

Formula Total number of persons in a row or class = (Rank of a person from upper end or left end) + (Rank of that person from lower or right end) - 1