Quiz Discussion

There are three rooms in a motel: one single, one double, and one for four persons. How many ways are there to house seven persons in these rooms?

• 1]

  7! / 1! 2! 3! 

• 2]

  7! 

• 3]

  7! / 3

• 4]

  7! / 3!

Ten participants are participating in a competition. In how many ways can the first three prizes be won?

• 1]

  920

• 2]

  680

• 3]

  720

• 4]

  820

How many rectangles can be formed out of a chess board ?

• 1]

  1740

• 2]

  1230

• 3]

  1296

• 4]

  204

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

In how many ways can 10 people line up at a ticket window of a railway station?

• 1]

  36,28,800

• 2]

  34,82,800

• 3]

  33,44,800

• 4]

  33,28,800

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 box contains 5 green, 4 yellow and 3 white marbles. three marbles are drawn at random. What is the probability that all they are not of the same colour?

• 1]

  3/44

• 2]

  3/55

• 3]

  52/55

• 4]

  41/44

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

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

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?

• 1]

  159

• 2]

  194

• 3]

  205

• 4]

  209