An electrical device can be minor defective in 10 ways and major defective in 8 ways. In how many ways 2 major and 2 minor defects can occur?
5040
1260
164
80
If 12Pr=11P6+6. 11P5, then the value of r is
3
6
9
12
How many three -letter words can be formed from the alphabets a, b, c, d and e, if repetition is not allowed?
5
25
60
100
The no. of ways of answering 5 objective type questions, when each question has 4 choices , is
16
256
1024
Among the 36 teachers in a school, one principal and one vice principal are to be appointed. In how many ways this can be done?
1060
1160
1206
The no. of 5 digit numbers that can be formed with the digits 0,1,2,3,4 if the numbers can be repeated in the same number is
250
2500
12500
In how many ways can 4 boys and 3 girls be seated in a row of 7 chairs, if the boys and girls have to sit alternate?
120
144
288
The no. of way in which the letters of the word 'ARRANGE' can be arranged such that both 'R' do not come together is
360
900
1620
A polygon has 44 diagonals. The no. of its sides is
11
7
8
If repetition of numbers is allowed, then the no. of ways in which three even digit natural numbers can be formed is
350
450
550
