Out of 100 students,two sections of 40 and 60 are formed.If you and your friend are among the 100 students,what is the probability that
(a) you both enter the same section ?( b) you both enter the different section?

In a class of 100 students 60 drinks tea. 50 drink coffee and 30 drink both .A students from this class is selected at random.Find the probability that the student takes (i) atleast one of the two drinks (ii) only one of the two drinks

The following table gives the distribution of students of two sections according to the marks obtained by them : Represent the marks of the students of both the sections on the same graph by two frequency polygons. From the two polygons compare the performance of the two sections.

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.

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.

In test-tubes A and B , zinc sulphate solution and silver nitrate solution are taken respectively . Copper trunings are added to both test-tubes . In which of the two test-tubes do you observe the reaction. Justify your answer with scientific reason.

In a hostel, 60% of the students read Hindi newspaper, 40% read English newspaper and 20% read both Hindi and English newspapers. A student is selected at random. (a) Find the probability that she reads neither Hindi nor English newspapers. (b) If she reads Hindi newspaper, find the probability that she reads English newspaper (c) If she reads English newspaper, find the probability that she reads Hindi newspaper.

Form the pair of linear equations in the following problems and find their solutions (if they exist) by any algebraic method : Places A and B are 100 km apart on highway. One car starts from A and another form B at the same time. If the cars travel in the same direction at different speeds, they meet in 5 hours. If they travel towards each other, they meet in 1 hour. What are the speeds of the two cars ?