A box contains 2 white balls, 3 black balls and 4 red balls. In how many ways can 3 balls be drawn from the box, if at least one black ball is to be included in the draw ? By Editor No Comment Answer : C. 64
How many words can be formed from the letters of the word “AFTER”, so that the vowels never come together ? By Editor No Comment Answer : C. 72
Out of 7 consonants and 4 vowels, how many words of 3 consonants and 2 vowels can be formed ? By Editor No Comment Answer : C. 25200
