how many permutation of the letters PQRSTUVWX contain the string VWX or WX
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I know how to calculate each task like the following 7! + 8! but I am not sure how to subtract the overlapping part usually, it will the (or) parts is between distinct string, but in this example, they share 2 letters how do I solve this?
discrete-mathematics permutations
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asked Nov 16 at 15:36
Nour M Al-S
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If the permut...