Math Is Fun Forum

Carisma

Member

Registered: 2010-01-08

Posts: 10

Permutation question

A committee of five people is to be chosen from 5 married couples. In how many ways can the committee be chosen if:

a. the committee mus contain at least one man and one woman
b. the committee must contain the youngest man
c. both husband and wife cannot be on the committee

I've managed to do the 1st 2 parts but for some reason I keep getting the last part wrong...the answer's 32 and I'm getting something different.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,466

Re: Permutation question

Hi Carisma,

A committee of five people is to be chosen from 5 married couples. In how many ways can the committee be chosen if:

c. both husband and wife cannot be on the committee

I thought I could do these questions easily but I'm getting an answer in 3 figures (?).

Help me out here.  What answers did you get for a and b?

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Permutation question

Hi all;

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Carisma

Member

Registered: 2010-01-08

Posts: 10

Re: Permutation question

Hi all;

Hi Bobby,

Thanks for this! I always tend to over complicate things with these permutation questions.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Permutation question

Hi Carisma;

Okay, no problem. I do it too, combinatorics is the hardest problems there are. Easy to get balled up on them.

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

soroban

Member

Registered: 2007-03-09

Posts: 452

Re: Permutation question

. .

.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,466

Re: Permutation question

Thanks guys;  I should have got that! I feel such a fool.:

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob