How many ways are possible to arrange 4 boys and 3 girls for a dinner, if there are two straight ben

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30 Apr 2021 arrangement

How many ways are possible to arrange 4 boys and 3 girls for a dinner, if there are two straight benches of capacity 5 and 2 persons for their sitting?

OPtion

1) 720
2) 5040
3) 2520
4) 840
5) 4320
6) 2460
7) 2860
8) 120
9) 24
10) None of the above

Solution

Total no. of persons = 7
Since benches are straight, therefore arranging them in benches of capacity 5 and 2 persons is
equivalent to arranging them in a straight bench of capacity 7 persons.
Total no. of methods
= 7*6*5*4*3*2*1 = 5040

Correct Option: 2 Best Solution (1)