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Determine the number of arrangements where 6 boys and 3 girls can be seated in a row, ensuring at least two girls sit together, while the boys can be in any order.

Option: 1

9652


Option: 2

1000


Option: 3

9604


Option: 4

5208


Answers (1)

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To determine the number of arrangements where 6 boys and 3 girls can be seated in a row, ensuring at least two girls sit together, we can consider the following cases:

Case 1: Two girls sit together:

In this case, we can treat the two girls who sit together as a single entity. This reduces the problem to arranging 7 entities: the combined entity of the two girls, the remaining girl, and the 6 boys. These 7 entities can be arranged in 7!= 5,040 ways.

Case 2: All three girls sit together:

In this case, we treat the three girls who sit together as a single entity. This reduces the problem to arranging 4 entities: the combined entity of the three girls and the 6 boys. These 4 entities can be arranged in 4!= 24 ways.

Case 3: Two pairs of girls sit together:

In this case, we can consider the two pairs of girls as single entities. This reduces the problem to arranging 5 entities: the combined entity of the two pairs of girls, the remaining girl, and the 6 boys. These 5 entities can be arranged in  5!= 120 ways.

Case 4: All three girls sit together and one girl sits separately:

In this case, we treat the three girls who sit together as a single entity and the remaining girl as a separate entity. This reduces the problem to arranging 4 entities: the combined entity of the three girls, the remaining girl, and the 6 boys. These 4 entities can be arranged in 4!= 24 ways.

Total number of arrangements = (Number of arrangements in Case 1) + (Number of arrangements in Case 2) + (Number of arrangements in Case 3) + (Number of arrangements in Case 4)

= 5,040 + 24 + 120 + 24

= 5,208

Therefore, there are 5,208 different arrangements where 6 boys and 3 girls can be seated in a row, ensuring at least two girls sit together, while the boys can be in any order.

 

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Gaurav

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