Advertisements
Advertisements
प्रश्न
In how many ways can 10 examination papers be arranged so that the best and the worst papers never come together?
विकल्प
9 × 8!
8 × 8!
9 × 9!
8 × 9!
उत्तर
8 × 9!
Explanation:
Arrange 8 papers in 8! ways and two papers in 9 gaps are arranged in 9P2 ways.
Required number = 8! 9P2
= 8! × 9 × 8
= 9! × 8
APPEARS IN
संबंधित प्रश्न
Evaluate: 8!
Evaluate: 10!
Evaluate: 10! – 6!
Compute: `(12!)/(6!)`
Compute: `(12/6)!`
Compute: 3! × 2!
Compute: `(9!)/(3! 6!)`
Compute: `(6! - 4!)/(4!)`
Compute: `(8!)/(6! - 4!)`
Write in terms of factorial.
5 × 6 × 7 × 8 × 9 × 10
Write in terms of factorial.
3 × 6 × 9 × 12 × 15
Evaluate `("n"!)/("r"!("n" - "r")!)` for n = 15, r = 10
Evaluate : `("n"!)/("r"!("n" - "r")!)` for n = 15, r = 8
Find n, if `(1!)/("n"!) = (1!)/(4!) - 4/(5!)`
Find n, if (n + 1)! = 42 × (n – 1)!
Find n, if (n + 3)! = 110 × (n + 1)!
Find n, if: `((15 - "n")!)/((13 - "n")!)` = 12
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
Show that `(9!)/(3!6!) + (9!)/(4!5!) = (10!)/(4!6!)`
Show that `((2"n")!)/("n"!)` = 2n (2n – 1)(2n – 3) ... 5.3.1
Simplify `((2"n" + 2)!)/((2"n")!)`
Simplify `1/("n"!) - 1/(("n" - 1)!) - 1/(("n" - 2)!)`
Simplify n[n! + (n – 1)!] + n2(n – 1)! + (n + 1)!
Simplify `("n" + 2)/("n"!) - (3"n" + 1)/(("n" + 1)!)`
Simplify `1/(("n" - 1)!) + (1 - "n")/(("n" + 1)!)`
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?
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
Select the correct answer from the given alternatives.
Find the number of triangles which can be formed by joining the angular points of a polygon of 8 sides as vertices.
Eight white chairs and four black chairs are randomly placed in a row. The probability that no two black chairs are placed adjacently equals.
Find the number of integers greater than 7,000 that can be formed using the digits 4, 6, 7, 8, and 9, without repetition: ______
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 ______.
