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Find n, if \(2n-1 Pn : 2n+2Pn-1=22:7\)

User SNBS
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Final answer:

To find the value of n, set up an equation based on the given ratio of two permutations and solve for n using the permutation formulas and algebraic manipulation.

Step-by-step explanation:

The question is asking to find the value of n given the ratio of two permutations, 2n-1 P n to 2n+2 P n-1, is equal to 22:7. To solve this, we need to set up an equation using the definition of permutations and solve for n.

To calculate a permutation, you use the formula n P k = n! / (n-k!), where n! means the factorial of n and k is the number of items being chosen. The ratio given in the problem is 22:7, so we have:

(2n-1 P n) / (2n+2 P n-1) = 22 / 7

Substitute the permutation formula:

((2n-1)! / ((2n-1-n)! n!)) / ((2n+2)! / ((2n+2-(n-1))! (n-1)!)) = 22 / 7

This expression can be simplified and solved for n through algebraic manipulation. The solution involves factorials and possibly cancellation of terms.

User Dradd
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