In a group of 6 boys and 4 girls, four children are to be selected. In how many different ways can they be selected such that at least one boy should be there?
159
194
205
209
The number of different four digit numbers that can be formed with the digits 2,3,4,5,7 using each digit only once is.
4!
4 (4!)
5!
5 (7!)
In how many different ways can the letters of the word 'LEADING' be arranged in such a way that the vowels always come together?
360
480
720
5040
From a group of 7 men and 6 women, five persons are to be selected to form a committee so that at least 3 men are there on the committee. In how many ways can it be done?
564
645
735
756
In how many ways a committee, consisting of 5 men and 6 women can be formed from 8 men and 10 women?
266
11760
86400
In how many different ways can the letters of the word 'MATHEMATICS' be arranged so that the vowels always come together?
10080
4989600
120960
None of these
In how many ways can the letters of the word 'LEADER' be arranged?
72
144
In how many different ways can the letters of the word 'OPTICAL' be arranged so that the vowels always come together?
120
4320
2160
If nP5 = 60 .n - 1P3 , then n is.
6
15
10
12
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?
32
48
64
96
