In a class of 35 students, 17 have taken mathematics, 10 have taken mäthematics but not economics. Find the number of students who have 'taken both mathematics and economics and the number of students who hive taken economics but not mathematics, if it is given that each students has taken either mathematics.or economics òr both,

The number of students who take both the subjects Mathematics and Chemistry is 30. This represents 10% of the enrolment in Mathematics and 12% of the enrolment in Chemistry. How many students take atleast one of these two subjects ?

In a class, in an examination in Mathematics, 10 students scored 100 marks each 2 students scored zero and the average of the remaining students is 72 marks. If the class average is 76, then the number of students in the class is

In class XI of a school 40% of the students study Mathematics and 30% study Biology, 10% of the class study both Mathematics and Biology. If a student is selected at random from the class, find the probability that he will be studying mathematics or Biology.

A box contains slips numbered prime numbers from 1 to 10 and another box contains odd numbers from 1 to 10 . If one slips taken from each. a) What is the probability of both being prime numbers?

There are 50 children ina class.Thirty of them are girls . There are 40 children in another class. 25 of them are boys.One student is taken from each class at random. What is the number of outcomes ? How many out comes contain both boys. How many outcomes contain both girls. How many out comes have one boy and one girl.

During a seminar session in the class , the presenter argued that equal amounts of both H_2 and N_2 on heating at constant pressure will expand in the same rate. Another student objected this argument by saying that they will expand differently since their molecular masses are different . c)State the law and give its mathematical expresssion.

Write the negation of the following statements: (i) p: For every real number x , x^(2)gt(x) (ii) q: There exists a rational number x such that x^2=2 . (iii) r: All birds have wings. (iv) s : All students study mathematics at the elementary level.