Quiz Discussion

The number of triangles that can be formed by choosing the vertices from a set of 12 points, seven of which lie on the same straight line, is

• 1]

  185

• 2]

  175

• 3]

  115

• 4]

  105

It is required to seat 5 boys and 4 girls in a row so that the girls occupy the even places. How many such arrangements are possible?

• 1]

  2880

• 2]

  2148

• 3]

  3280

• 4]

  3680

If C(n, 7) = C(n, 5), find n

• 1]

  12

• 2]

  15

• 3]

  18

• 4]

  -1

A number lock on a suitcase has 3 wheels each labeled with 10 digits from 0 to 9. If the opening of the lock is a particular sequence of three digits with no repeats, how many such sequences will be possible?

• 1]

  720

• 2]

  760

• 3]

  780

• 4]

  680

How many integers between 1000 and 10000 have no digits other than 4, 5, or 6?

• 1]

  91

• 2]

  71

• 3]

  51

• 4]

  81

If (n + 2)! = 2550 (n!); find ’n’

• 1]

  49

• 2]

  35

• 3]

  38

• 4]

  43

A, B, C, D and E sit on five chairs all of which are facing north. C will sit only on the leftmost chair and B will not sit anywhere to the left of A. In how many ways they can be seated?

• 1]

  10

• 2]

  18

• 3]

  36

• 4]

  12

How many parallelograms will be formed if 7 parallel horizontal lines intersect 6 parallel vertical lines?

• 1]

  42

• 2]

  294

• 3]

  315

• 4]

  258

A biased coin in tossed thrice. What is the probability that heads turns out at least twice considering that the probability of a head is 60%?

• 1]

  0.648

• 2]

  0.234

• 3]

  0.348

• 4]

  .839

12 person are seated at a round table. Number of ways of selecting 2 persons not adjacent to each other is

• 1]

  10

• 2]

  11

• 3]

  54

• 4]

  48