Question
In a group of 8 girls, two girls are sisters. The number of ways in which the girls can sit so that two sisters are not sitting together is

4820

1410

2830

None of these
easy
Solution
None of these
The required number of ways
= the number of ways in which 8 girls can sit – the number of ways in which two sisters are together
= 8! – (2) (7!) = 30240.
SIMILAR QUESTIONS
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