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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: 8!
Evaluate: 10! – 6!
Evaluate: (10 – 6)!
Compute: `(12!)/(6!)`
Compute: `(12/6)!`
Compute: (3 × 2)!
Compute: `(9!)/(3! 6!)`
Compute: `(8!)/(6! - 4!)`
Compute: `(8!)/((6 - 4)!)`
Write in terms of factorial.
5 × 10 × 15 × 20
Evaluate : `("n"!)/("r"!("n" - "r")!)` for n = 8, r = 6
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Find n, if `"n"/(6!) = 4/(8!) + 3/(6!)`
Find n, if (n + 1)! = 42 × (n – 1)!
Find n, if: `((15 - "n")!)/((13 - "n")!)` = 12
Find n, if: `((2"n")!)/(7!(2"n" - 7)!) : ("n"!)/(4!("n" - 4)!)` = 24 : 1
Show that `("n"!)/("r"!("n" - "r")!) + ("n"!)/(("r" - 1)!("n" - "r" + 1)!) = (("n" + 1)!)/("r"!("n" - "r" + 1)!)`
Show that `(9!)/(3!6!) + (9!)/(4!5!) = (10!)/(4!6!)`
Simplify `((2"n" + 2)!)/((2"n")!)`
Simplify `(("n" + 3)!)/(("n"^2 - 4)("n" + 1)!)`
Simplify `1/("n"!) - 1/(("n" - 1)!) - 1/(("n" - 2)!)`
Simplify `("n"^2 - 9)/(("n" + 3)!) + 6/(("n" + 2)!) - 1/(("n" + 1)!)`
Select the correct answer from the given alternatives.
In how many ways can 8 Indians and, 4 American and 4 Englishmen can be seated in a row so that all person of the same nationality sit together?
In how many ways can 10 examination papers be arranged so that the best and the worst papers never come together?
Find the number of integers greater than 7,000 that can be formed using the digits 4, 6, 7, 8, and 9, without repetition: ______
If `((11 - "n")!)/((10 - "n")!) = 9,`then n = ______.
3. 9. 15. 21 ...... upto 50 factors is equal to ______.
Let Tn denote the number of triangles which can be formed using the vertices of a regular polygon of n sides. If Tn + 1 – Tn = 21, then n is equal to ______.
