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प्रश्न
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
विकल्प
12
288
144
256
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उत्तर
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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संबंधित प्रश्न
Evaluate: 10!
Evaluate: 10! – 6!
Evaluate: (10 – 6)!
Compute: (3 × 2)!
Compute: 3! × 2!
Compute: `(9!)/(3! 6!)`
Compute: `(6! - 4!)/(4!)`
Compute: `(8!)/((6 - 4)!)`
Write in terms of factorial.
3 × 6 × 9 × 12 × 15
Write in terms of factorial.
6 × 7 × 8 × 9
Write in terms of factorial.
5 × 10 × 15 × 20
Evaluate : `("n"!)/("r"!("n" - "r")!)` for n = 12, r = 12
Evaluate `("n"!)/("r"!("n" - "r")!)` for n = 15, r = 10
Find n, if `"n"/(8!) = 3/(6!) + (1!)/(4!)`
Find n, if `"n"/(6!) = 4/(8!) + 3/(6!)`
Find n, if `(1!)/("n"!) = (1!)/(4!) - 4/(5!)`
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Find n, if (n + 3)! = 110 × (n + 1)!
Find n, if: `("n"!)/(3!("n" - 3)!) : ("n"!)/(5!("n" - 7)!)` = 1 : 6
Find n, if: `((2"n")!)/(7!(2"n" - 7)!) : ("n"!)/(4!("n" - 4)!)` = 24 : 1
Simplify `(("n" + 3)!)/(("n"^2 - 4)("n" + 1)!)`
Simplify `1/("n"!) - 1/(("n" - 1)!) - 1/(("n" - 2)!)`
Simplify n[n! + (n – 1)!] + n2(n – 1)! + (n + 1)!
Simplify `1/("n"!) - 3/(("n" + 1)!) - ("n"^2 - 4)/(("n" + 2)!)`
Simplify `("n"^2 - 9)/(("n" + 3)!) + 6/(("n" + 2)!) - 1/(("n" + 1)!)`
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