Answer-Six students are to be seated in a row. Four of them are boys and the rest are girls. In how many wa...

Q: Answer-Six students are to be seated in a row. Four of them are boys and the rest are girls. In how many wa...

6 students can be arranged among themselves in 6P6 ways 720 ways. Assume that the 2 girls are one entity. The total number of ways in which they can be arranged among themselves 2 2 ways. Also, the set of two girls and the other students can be arranged among themselves 5 120 ways. Thus, total number of ways in which two girls are together 120 2 240 Thus, number of ways in which the 2 girls will not sit together 720 240 480

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Accepted Answer

6 students can be arranged among themselves in 6P6 ways = 720 ways.
Assume that the 2 girls are one entity. The total number of ways in which they can be arranged among themselves = 2! = 2 ways.
Also, the set of two girls and the other students can be arranged among themselves = 5! = 120 ways.
Thus, total number of ways in which two girls are together = 120 × 2 = 240
Thus, number of ways in which the 2 girls will not sit together = 720 − 240 = 480

Six students are to be seated in a row. Four of them are

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