Permutation and CombinationHard
Question
m parallel lines in a plane are intersected by a family of n parallel lines. The total number of parallelograms so formed is-
Options
A.
B.
C.
D.
More Permutation and Combination Questions
In how many ways 4 paintings can be hung on 4 walls of a room so that (i) one painting is hung on each wall and (ii) any...In a football championship, 153 matches were played. Every team played one match with each other. The number of teams pa...How many cricket eleven can be formed from 15 persons if captain is included in every team?...How many signals can be given by means of 10 different flags when at a time 4 flags are used, one above the other?...In how many ways 7 different beads be strung into a ring so that two particular beads are always together?...