In the next world cup of cricket, there will be 12 teams divided equally into two equal groups. Team of each group will play a match against other teams of the group. From each group, 3 top teams will qualify for next round. In this round, each team will play against each other. Four top teams of this round will qualify for semifinals and play against each other and then two top teams will go to final where they play the best of three matches. How much minimum number of matches in the next world cup will be?

A polygon has 14 diagonals then the number of sides are

The number of four-letter words can be formed using the letters of the word DICTIONARY is

The number of words that can be formed using the letters of the "PETROL" such that the words do not have "P" in the first position, is

The no. of different ways the letters of the word "DETAIL" can be arranged in such a way that the vowels can occupy only the odd position is

The value of $N$ in $N! + \frac{1}{7!} = \frac{1}{8!}$ is

There are ten flights operating between city A and city B. The number of ways in which a person can travel from city A to city B and return by different flight is: