Mathematics: Tips for Solving Ranking Test Problems in Competitive Exams

Tips to Solve Ranking Test Problems

The process of determining the position or place of a person or a thing on the basis of comparison or relative position of other person or things is called ranking. In this type of questions, relative positions or ranking of different groups of persons or objects is given. Students are required to establish the ranking or position of other individuals in the same group with respect to one another.

The given information are scattered and puzzled. You have to arrange them systematically and then given the answer. How to arrange the informations has been discussed in the previous chapter.

Practice Question:

1) In a row of girls, "Gauri" is 11th from each end. How many girls are there in the row ?

Solution:- Gauri's rank is 11th from each end means she is 11th from the right end and also from the left end. Since, she is 11th from each end, if can be said. There are 10 girls on each side of Gauri.

 

   10                10

|------------|-------------|

            Gauri

Total number of girls = 10 + Gauri + 10 = 21.

This question can be solved by formula also, 

Total number of girls = (Rank from left) + (Rank from right) -1 

                                = 11 + 11 -1 = 21.

Formulas for Solving Ranking Problems in Row (or) in a Class

Formula 1:- 

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

Formula 2:- 

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

Formula 3:- 

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

Sample Problem:

1) In a class of 52 students, Shaker's rank is 14th from the top. What is his rank from the bottom?

 Solution:- By Formula;

         

    Shaker's rank from the bottom = (Total number of students in class) - (Shaker's rank from the top) + 1

                                                       = 52 - 14 + 1= 53 - 14 = 39th

Second Method:

Total number of students is 52 in the class. Shaker's rank is 14th from the top means there are 13 students before him.

           

            13                       (x)

|-------------------|---------------------|

                    Shaker's

Total number of students = 52 = 13 + 1 + x = 14 + x

                                          52 = 14 + x

                                           x = 52 - 14 = 38

Since, 38 students are below Shaker's means his rank is 39th from the bottom