Combanatorics Problem (Probability Application)

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Homework Statement

From a load of 50 Panasonic tape recorders 35 are destined for L.A. and 15 are destined fro Miami. If two are shipped to Trenton by mistake and the "selection" is made at random, determine the probabilities that:

a) both should have gone to L.A.

b) one should have gone to L.A. and the other to Miami



Homework Equations





The Attempt at a Solution

Alright, I think I'm starting to get the hang of these. But I want to bounce this one off of somebody to get a second set of eyes on it.

For P(both to L.A.) I am getting (35 choose 2)/(50 choose 2) = 0.4857

For P(one to each city) I am getting [(35 choose 1)(15 choose 1)]/(50 choose 2) = 0.4286
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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