Quiz Discussion

In how many different ways can the letters of the word 'OPTICAL' be arranged so that the vowels always come together?

• 1]

  120

• 2]

  720

• 3]

  4320

• 4]

  2160

A polygon has 44 diagonals. What is the number of its sides?

• 1]

  7

• 2]

  8

• 3]

  9

• 4]

  11

In a single throw with four dice,the probability of throwing seven is

• 1]

  20/6⁴

• 2]

  24/6⁵

• 3]

  22/8⁴

• 4]

  24/8⁴

Six boys and 4 girls are to be seated in two separate rows with five chairs each, such that two particular girls are always together and all the girls are not in the same row. In how many ways can they be seated?

• 1]

  15 * 7!

• 2]

  20 * 8!

• 3]

  18 * 7!

• 4]

  (16 * 8! – 4! * 6!)

The students in a class are seated, according to their marks in the previous examination. Once, it so happens that four of the students got equal marks and therefore the same rank. To decide their seating arrangement, the teacher wants to write down all possible arrangements one in each of separate bits of paper in order to choose one of these by lots. How many bits of paper are required?

• 1]

  24

• 2]

  12

• 3]

  36

• 4]

  48

If (n + 2)! = 2550 (n!); find ’n’

• 1]

  49

• 2]

  35

• 3]

  38

• 4]

  43

In how many different ways can the letters of the word 'CORPORATION' be arranged so that the vowels always come together?

• 1]

  50400

• 2]

  2430

• 3]

  6540

• 4]

  12800

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

• 1]

  42

• 2]

  294

• 3]

  315

• 4]

  258

The number of circles that can be drawn out of 10 points of which 7 are collinear is

• 1]

  130

• 2]

  85

• 3]

  45

• 4]

  72

If ¹⁸C_r = ¹⁸C_r+2 ; find ^rC₅.

• 1]

  56

• 2]

  63

• 3]

  49

• 4]

  42