How many diagonals can be drawn in a pentagon?

In how many different ways can the letters of the word CORPORATION be arranged so that the vowels may occupy only the od…

When six fair coins are tossed simultaneously, in how many of the outcomes will at most three of the coins turn up as he…

The letter of the word LABOUR are permuted in all possible ways and the words thus formed are arranged as in a dictionar…

In how many different ways can the letters of the word 'OPTICAL' be arranged so that the vowels always come together?

In how many different ways can the letters of the word TOTAL be arranged?

How many arrangements of four 0's (zeroes), two 1's and two 2's are there in which the first 1 occur before the first 2?

a, b, c, d and e are five natural numbers. Find the number of ordered sets (a, b, c, d, e) possible such that a + b + c …