Recent questions tagged counting

Five teams have to compete in a league, with every team playing every other team exactly once, before going to the next round. How many matches will have to be held to c...

To pass a test, a candidate needs to answer at least $2$ out of $3$ questions correctly. A total of $6,30,000$ candidates appeared for the test. Question $A$ was correctl...

A set of $4$ parallel lines intersect with another set of $5$ parallel lines. How many parallelograms are formed?$20$$48$$60$$72$