## Question

### Solution

Correct option is The total number of cases is 6 × 6 × 6 = 63 = 216. The number of favorable ways

= coefficient of xk in (x + x2 +…….+ x6)3

= coefficient of xk – 3 in (1 – x6)3 (1 – x) – 3

= coefficient of xk – 3 in (1 – x) – 3                 [∴ 0 ≤ k – 3 ≤ 5]

= coefficient of xk – 3 in  Thus, the probability of the required event is (k – 1) (k – 2)/432

#### SIMILAR QUESTIONS

Q1

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Q2

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Q3

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Q6

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S2 : A and B ∩ C are independent

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Q10

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