A box contains 10 balls out of which 3 are red and rest are blue. In how many ways can a random sample of 6 balls be drawn from the bag so that at the most 2 red balls are included in the sample and no sample has all the 6 balls of the same colour?
A. 105
B. 168
C. 189
D. 120
Answer: Option B
Solution(By Examveda Team)
Six balls can be selected in the following ways, One red ball and 5 blue balls Or Two red balls and 4 blue balls. Total number of ways, = (3C1 × 7C5) + (3C2 × 4C7)= 63 + 105
= 168
Related Questions on Permutation and Combination
A. 3! 4! 8! 4!
B. 3! 8!
C. 4! 4!
D. 8! 4! 4!
A. 7560,60,1680
B. 7890,120,650
C. 7650,200,4444
D. None of these
A. 8 × 9!
B. 8 × 8!
C. 7 × 9!
D. 9 × 8!
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