On a new year day every student of a class sends a card to every other student. The post man delivers 600 cards. How many students are there in the class?

There are 45 students in a class and 3/5 of them are boys. How many girls are there in the class?

On the event of new year each student of class XI sends cards to his classmates. If there are 40 students in the class number of cards exchanged during the process is

Joseph , the primary school teacher of Illinois Public School , distributed some sweets among the students of his class on his birthday . After distributing three sweets to every student, he found some sweets were still left over with him . He doubled the number of sweets with each student and found that he still had M sweets left over. However, instead of doubling, had he given only one sweet extra to every student , he would have been left with N sweets (N gt M) . How many students are there is his class ?

On the occasion if Deepawali festival, each student in a class sends greeting cards to other. If there are 20 students in the class, find the total number of greeting cards exchanged by the students?

At City High School, the sophomore class has 60 numbers than the freshman class. The junior class has 50 fewer students than twice the students in the freshman class. The senior class is three times as large as the freshman class. If there are a total of 1,424 students at City High School, how many students are in the freshman class?

The following histogram depicts the marks obtained by 45 students of a class: Figure: Look at the histogram and answer the following questions: What is the class size? How many students obtained less than 10 marks? How many students obtained 30 or more marks but less than 40? What is the interval of highest marks and how many students are there in this interval? If passing marks are 30, what is the number of failures?

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?

In mid-day meal scheme 3/(10) litre of milk is given to each student of a primary school. If 30 litre of milk is distributed every day in the school, how many students are there in the school?

In a class, 70 students wrote two tests wiz, test-I and test-II 50% of the students failed in test I and 40% of the students in test -II. How many students passed in both tests?