Permutation-Combination

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Three flags, each of different colour, are available for a military exercise. Using these flags, different codes can be generated by waving
(i) single flag of different colours, or
(ii) any two flags in a different sequence of colours, or
(iii) three flags in a different sequence of colours.
The maximum number of codes that can be generated is...........
6
no
9
no
15
yes
18
no
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Each of the 3 persons is to be given identical items such that product of the numbers of items received by each of the three persons is equal to 30. In how many maximum different ways can this distribution be done?
21
no
24
no
27
yes
33
no
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A bag contains 20 balls. 8 balls are green, 7 are white and 5 are red. What is the minimum number of balls that must be picked up from the bag blind-folded (without replacing any of it) to be assured of picking atleast one ball of each colour?
4
no
7
no
11
no
16
yes
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Five balls of different colours are to be placed in three different boxes such that any box contains at least one ball. What is the maximum number of different ways in which this can be done?
90
no
120
no
150
no
180
yes
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Rohit has five friends: 3 girls and 2 boys. Rohit's wife also has 5 friends: 3 boys and 2 girls. In how many maximum number of different ways can they invite 2 boys and 2 girls such that two of them are Rohit's friends and two are his wife's?
24
no
38
no
46
yes
58
no
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There are 240 balls and n number of boxes B1, B2, B3, Bn. The balls are to be placed in the boxes such that B1 should contain 4 balls more than B2, B2 should contain 4 balls more than B3, and so on. Which one of the following cannot be the possible value of n?
4
no
5
no
6
no
7
yes
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A schoolteacher has to select the maximum possible number of different groups of 3 students out of a total of 6 students. In how many groups any particular student will be included?
6
no
8
no
10
yes
12
no
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A person has 4 coins each of different denomination. What is the number of different sums of money the person can form (using one or more coins at a time)?
16
no
15
yes
12
no
11
no
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How many three-digit numbers can be generated from 1, 2, 3, 4, 5, 6, 7, 8, 9 such that the digits are in ascending order?
80
no
81
no
83
no
84
yes
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In how many different ways can six filmstars be arranged in a line such that two of them, Shahrukh and Salman, are never together?
120
no
240
no
360
no
480
yes
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