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6.
There are n teams participating in a football championship. Every two teams played one match with each other. There were 171 matches on the whole. What is the value of n?
- A.21
- C.17
- B.19
- D.15
- Answer & Explanation
- Report
Answer : [B]
Explanation :
Explanation :
Total number of matches played = nC2 | |||||
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7.
How many words can be formed from the letters of the word AKHILESH, so that the vowels are always together?
- A.2160
- C.2140
- B.3620
- D.360
- Answer & Explanation
- Report
Answer : [A]
Explanation :
Explanation :
In the given word, AKHILESH, we treat the vowels AIE as one letter. | ||||||
Thus, we have KHLSH (AIE) | ||||||
This group has 6 letters of which H occurs 2 times and other letters are different. | ||||||
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Now 3 vowels can be arranged among themselves in 3! = 6 ways | ||||||
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8.
5 men and 5 women sit around a circle table, the men and women alternately. In how many different ways can the seating arrangement be made?
- A.2800
- C.10!
- B.2880
- D.9!
- Answer & Explanation
- Report
Answer : [B]
Explanation :
Explanation :
5 men can be arranged in a circular table in 4! Ways = 24 ways |
There are 5 seats available for the five women |
They can be arranged in 5! Ways |
The number of ways in which the men and women can be seated = 5! X 4! Ways = 2880 ways. |
9.
There are 6 boxes labeled A, B, C, D, E and F. In each box a black or a white ball is to be put in such a manner that at least one box contains a black ball and the boxes containing black balls are labeled with consecutive letters. The total number of ways in which this can be done is
- A.21
- C.20
- B.19
- D.26
- Answer & Explanation
- Report
Answer : [A]
Explanation :
Explanation :
The boxes containing the black balls can be as follows: | ||||||||||||||||||||||||||||||||||||||||||||||||
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10.
In how many ways can 7 MBA and 5 MCA students be seated in a row so that no two of the MCA students may sit together?
- A.7! 8!
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C.
7! 8! 3!
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B.
7! 8! 2! - D.56
- Answer & Explanation
- Report
Answer : [C]
Explanation :
Explanation :
There are no restriction on MBA Students | |||||||||
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|x| MBA |x| MBA |x| MBA |x| MBA |x| MBA |x| MBA |x| MBA |x| | |||||||||
Now, if MCA students sit at the places (including the two ends) indicated by |x|, then no two of the 5 MCA students will come together. |
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There 8 places are filled by 5 MCA students in 8P5 ways. | |||||||||
The 7 MBA students can sit in a row in 7! Ways | |||||||||
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