Quiz Discussion

There are seven pairs of black shoes and five pairs of white shoes. They are all put into a box and shoes are drawn one at a time. To ensure that at least one pair of black shoes are taken out, what is the number of shoes required to be drawn out?

• 1]

  12

• 2]

  13

• 3]

  17

• 4]

  18

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

If A and B are two independent events with P(A) = 3/5 and P(B) = 4/9 , then P(A' ∩ B' ) equals

• 1]

  4/15

• 2]

  8/45

• 3]

  1/3

• 4]

  2/9

If A, B and C are mutually exclusive and exhaustive events of a random experiment such that P(B)=3/2​P(A) and P(C)=1/2​P(B), then P(A∪C)=

• 1]

  3/13

• 2]

  6/13

• 3]

  7/13

• 4]

  10/13

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!) 

If P(A)=2/5​, P(B)=3/10​ and P(A ∩ B) =51​, then P(A' | B'). P(B' | A') is equal to

• 1]

  5/6

• 2]

  5/7

• 3]

  25/42

• 4]

  1

How many words, with or without meaning, can be formed using all letters of the word EQUATION using each letter exactly once?

• 1]

  38,320

• 2]

  39,320

• 3]

  38,400

• 4]

  40,320

A fair coin is tossed 5 times. What is the probability of getting at least three heads on consecutive tosses?

• 1]

  3/16

• 2]

  1/4

• 3]

  7/24

• 4]

  5/16

There are 6 letters for 3 envelopes. In how many different ways can the envelopes be filled?

• 1]

  120

• 2]

  130

• 3]

  100

• 4]

  110

If ,​, are probabilities of three mutually exclusive events, then

• 1]

  

• 2]

  

• 3]

  

• 4]

  None Of These