P&C

A delegation of 5 students is to be formed from a group of 10 students. If 3 particular

students want to remain together whereas two particular students do not want to remain

together, then the number of selection is

(A) 10

(B) 20

(D) none

1 Answers

U missed one more case of not selecting the three students

This is the solution

Case 1 : selecting the three students

5C1 . 2C1

Case 2 : not selecting the three students

5C4 . 2C1

so ANS - 20

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