Set Theory Question(inclusion-exclusion principle related)

camcool21
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Homework Statement


An auto insurance has 10,000 policyholders. Each policyholder is classified as:
(i) young or old;
(ii) male or female;
(iii) married or single.
Of these policyholders, 3000 are young, 4600 are male, and 7000 are married. The policyholders can also be classi ed as 1320 young males, 3010 married males, and 1400 young married persons. Finally, 600 of the policyholders are young married males. How many of the company's policyholders are young, female, and single?

Homework Equations



|A \cup B| = |A| + |B| - |A \cap B|​

The Attempt at a Solution



Y = young, O = old
M = male, F = female
MR = married, S = single
n(Y) = 3000
n(O) = 10000 - 3000 = 7000,
n(M) = 4600,
n(F) = 10000 - 4600 = 5400
n(MR) = 7000
n(S) = 10000 - 7000 = 3000
n(Y∩M) = 1320
n(MR∩M) = 3010
n(Y∩MR) = 1400
n(Y∩MR∩M) = 600

Try to find n(Y∩F∩S)?

That's all I can get from the question. This is starred in my textbook as a difficult problem. Any thoughts?
 
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There is a few more you could write down. For instance, there are 3000 young people, and you know that 1320 of them are young males. Can you make a statement about how many young females there are, and then use this method to find other amounts?
 
Let ysm,osm,ymm,omm = number of young single males, old single males, young married males and old married males, respectively. Similarly, define ysf, osf, ymf,omf. You are given a total of 8 conditions involving these 8 variables.

RGV
 
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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