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In a monthly test, the teacher decides that there will be there questions, one each from ex. 7, 8 and 9 of the text book. There are 12 questions in ex-7 , 18 in ex-8 and 9 in ex-9. In how many ways can the three questions be selected?

Q: In a monthly test, the teacher decides that there will be there questions, one each from ex. 7, 8 and 9 of the text book. There are 12 questions in ex-7 , 18 in ex-8 and 9 in ex-9. In how many ways can the three questions be selected?

Number of ways selecting 1 question from ex-7 = 12C1 Number of ways selecting 1 question from ex-8 = 18C1 Number of ways selecting 1 question from ex-9 = 9C1 ∴ Total ways = 12C1 x 18C1 x 9C1 = 12 x 18 x 9 = 1944

1944
2094
1894
2194

Correct Answer: 1944

Explanation:

Number of ways selecting 1 question from ex-7 = ¹²C₁
Number of ways selecting 1 question from ex-8 = ¹⁸C₁
Number of ways selecting 1 question from ex-9 = ⁹C₁
∴ Total ways = ¹²C₁ x ¹⁸C₁ x ⁹C₁ = 12 x 18 x 9 = 1944

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