Quiz Discussion

A coin is tossed 5 times. What is the probability that head appears an odd number of times?

• 1]

  1/2

• 2]

  2/3

• 3]

  1/3

• 4]

  1

The value of  ⁷⁵P₂

• 1]

  5450

• 2]

  5555

• 3]

  5550

• 4]

  5656

How many four-digit numbers, each divisible by 4 can be formed using the digits 5, 6, 7, 8, 9, repetition of digits being allowed in any number?

• 1]

  75

• 2]

  100

• 3]

  125

• 4]

  150

A, B, C, and D are four points, any three of which are non-collinear. Then, the number of ways to construct three lines each joining a pair of points so that the lines do not form a triangle is

• 1]

  7

• 2]

  8

• 3]

  9

• 4]

  24

If ¹⁸C_r = ¹⁸C_r+2 ; find ^rC₅.

• 1]

  56

• 2]

  63

• 3]

  49

• 4]

  42

Two variants of the CAT paper are to be given to 12 students. In how many ways can the students be placed in two rows of six each so that there should be no identical variants side by side and that the students sitting one behind the other should have the same variant. Find the number of ways this can be done

• 1]

  2 x ¹²C₆ x (6!)²

• 2]

  2 x 6! x 6!

• 3]

  2 x ¹²C₆ x 6!

• 4]

  None of these

In how many ways can the letters of the word 'LEADER' be arranged?

• 1]

  360

• 2]

  720

• 3]

  120

• 4]

  None Of These

One red flower, three white flowers, and two blue flowers are arranged in a line such that
I. No two adjacent flowers are of the same color.
II. The flowers at the two ends of the line are of different colors.
In how many different ways can the flowers be arranged?

• 1]

  2

• 2]

  4

• 3]

  6

• 4]

  10

There are 8 orators A, B, C, D, E, F, G, and H. In how many ways can the arrangements be made so that A always comes before B and B always comes before C.

• 1]

  8! / 3!

• 2]

  8! / 6!

• 3]

  5! x 3!

• 4]

  8! / (5! x 3!) 

From among the 36 students in a class, one leader and one class representative are to be appointed. In how many ways can this be done?

• 1]

  1360

• 2]

  1060

• 3]

  1160

• 4]

  1260