#1 permutation problem

Hi Brent,

Thanks for the explanation. I arrived until the answer (70), but I again divide it by 12C4. I believe that this approach should be done for determining the total number of possibilities when it asks for probability right?

Can you please guide here.

Thank you,
Viju

viju9162 wrote:Hi Brent,

Thanks for the explanation. I arrived until the answer (70), but I again divide it by 12C4. I believe that this approach should be done for determining the total number of possibilities when it asks for probability right?

Can you please guide here.

Thank you,
Viju

That's correct. Had this been a probability question, we could use the formula:

Probability of desired outcome = Number of desired outcomes/number of total possible outcomes

in which 12C4 (the number of ways of selecting unordered subgroups of 4 from big group of 12) would be the denominator and 70 the numerator.

But in this question we don't care about the number of possible groups; instead, we just care about "how many of them" have 3 women and 1 man.

So, the key was the wording of the question. Because it is asking "how many" and because we are dealing with indivisible objects (people), we need a positive integer--not a proportion or fraction--in order to answer this question. If the question had asked for probability or fraction, then that would have been the correct aproach.

Thanks Testluv for the explanation .

I got the difference now.

Regards,
Viju