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01.

Find the number of ways of selecting a team of 6 people from a group of 10 people such that a particular person is always included in the team.

A.	⁹C₅	B.	⁹C₆
C.	¹⁰C₅	D.	¹⁰C₆

Answer and Explanation

Answer: ⁹C₅

Explanation:
Since a particular person has to be selected, we have to select only 5 persons from 9 persons which is possible in ⁹C₅

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02.

Find the number of even numbers formed using all the digits 1,2,3,4,5 when each digit occurs only once in each number

A.	6!	B.	2(4!)
C.	5!	D.	4!

Answer and Explanation

Answer: 2(4!)

Explanation:
A number is even if its units place is divisible by 2
=> Units place can be filled by either 2 or 4 i.e. in 2 ways
=> The remaining 4 places can be filled by the remaining 4 digits in 4! ways.
=> Total number of even numbers that can be formed = 2(4!) = 48

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