In a class, there are 45 students. On a new year eve, every student sends one greeting card to each of the other students. How many greeting cards were exchanged in all?

In a class there are 30 students. On the New year day, every student posts a greeting card to all his ther classmates. Find the total number of greeting cards posted by them.

In a class there are certain number of students. On the new year day every student posts a greeting card to all of his classmates. If the total number of greeting cards posted by them is 870. Then find the number of students.

On a new year day every student of a class sends a card to every other student. The postman delivers 600 cards. The number of students in the class are

On a new year day every student of a class sends a card to every other student.The postman delivers 600 cards.The number of students in the class are

in a class of 240 students , each student got sweets that are 15% of the total number of students. How many sweet were there ?

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?

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?

On the occasion of Deepawali festival, each student of a class sends greeting cards to the others. If there are 20 students in the class, then the total number of greeting cards exchanged by the students is

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?

On the occasion of Dipawali festival each student of a class sends greeting cards to the others . If there are 20 students in the class , then the total number of greeting cards exchanged by the students is