72% of 25 students are good in mathematics.How many are not good in mathematics?

In a class of 35 students, 17 have taken Mathematics , 10 have taken Mathematics but not Economics. Find the number of students who have taken Economics but not Mathematics , if the given that each student have taken either Mathematic or Economic or both.

A class has 175 students. The following table shows the number of students studying one or more of the following subjects in this case. How many students are enrolled in Mathematics alone, Physics alone and Chemistry alone? Are there students who have not offered any one of these subjects?

There are 4 students for physics, 6 students for chemistry and 7 students of mathematics gold medal. In how many ways one of these gold medals be awarded?

There are three books of physics, four of chemistry and five of mathematics. How many different collections can be made such that each collection consists of (i) one book of each subject (ii) atleast one book of each subject. (iii) atleast one book of mathematics.

There are 6 books on mathematics, 4 books on physics annd 5 books on chemistry in a book shop. The number of ways can a student purchase either a book on mathematics or a book on chemistry, is

In a school there are 20 teachers who teach mathematics or physics. Of these, 12 teach mathematics and 4 teach both physics and mathematics. How many teach physics ?

A teacher analyses the performance of two sections of students in a mathematics test of 100 marks given in the following table. Find the probability that a student obtained less than 20 in the mathematics test.

A teacher analyses the performance of two sections of students in a mathematics test of 100 marks given in the following table. Find the probability that a student obtained marks 60 or above.

From 50 students taking examinations in mathematics ,physics and chemistry ,37 passed mathematics, 24 physics and 43 chemistry. At most 19 passed mathematics and physics, at most 29 Mathematics and Chemistry and at most 20 Physics and Chemistry. The largest possible number that could have passed all three examinations is:

All the students of a class performed poolrly in mathematics which of the following statistical measures will not change evern after the grace marks were given