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Select the correct answer from the given alternatives. In how many ways 4 boys and 3 girls can be seated in a row so that they are alternate

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Question

Select the correct answer from the given alternatives.

In how many ways 4 boys and 3 girls can be seated in a row so that they are alternate

Options

  • 12

  • 288

  • 144

  • 256

MCQ
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Solution

144

Explanation;

B G B G B G B

4 boys take their seats in 4! ways 

3 girls take their seats in 3! ways

Required number = 4! × 3!

= 24 × 6

= 144

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Chapter 3: Permutations and Combination - Miscellaneous Exercise 3.1 [Page 67]

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Balbharati Mathematics and Statistics 2 (Arts and Science) [English] Standard 11 Maharashtra State Board
Chapter 3 Permutations and Combination
Miscellaneous Exercise 3.1 | Q I. (5) | Page 67

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