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प्रश्न
A teacher wants to select the class monitor in a class of 30 boys and 20 girls, in how many ways can the monitor be selected if the monitor must be a boy? What is the answer if the monitor must be a girl?
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उत्तर
Since the teacher wants to select a class monitor that must be a boy and there are 30 boys in a class.
∴ Total number of ways of selecting boy monitor
= 30 ways.
Since the teacher wants to select a class monitor that must be a girl and there are 20 girls in a class.
∴ Total number of ways of selecting girl monitor
= 20 ways.
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संबंधित प्रश्न
Evaluate: 6!
Compute: `(12/6)!`
Compute: 3! × 2!
Compute: `(6! - 4!)/(4!)`
Compute: `(8!)/((6 - 4)!)`
Write in terms of factorial:
3 × 6 × 9 × 12 × 15
Write in terms of factorial:
5 × 10 × 15 × 20 × 25
Evaluate: `("n"!)/("r"!("n" - "r"!)` For n = 8, r = 6
Find n, if `1/("n"!) = 1/(4!) - 4/(5!)`
Find n, if (n + 3)! = 110 × (n + 1)!
Find n if: `("n"!)/(3!("n" - 3)!) : ("n"!)/(5!("n" - 5)!)` = 5:3
Find n if: `("n"!)/(3!("n" - 5)!) : ("n"!)/(5!("n" - 7)!)` = 10:3
Find n, if: `((15 - "n")!)/((13 - "n")!)` = 12
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!)`
Find the value of: `(8! + 5(4!))/(4! - 12)`
Find the value of: `(5(26!) + (27!))/(4(27!) - 8(26!)`
Five balls are to be placed in three boxes, where each box can contain up to five balls. Find the number of ways if no box is to remain empty.
