Comments on: Brain Game: McLanderstone at the Movies

By: Isaac

Isaac — Mon, 01 Jun 2009 19:01:00 +0000

It’s a combination. 3 possible answers for 4 people. 3^4= 81. Yay, Algebra 2

By: Chan

Chan — Mon, 01 Jun 2009 17:24:00 +0000

I agree with the slightly ambiguous wording. I initially got a brain cramp worried about combinations versus permutations, then realized since there were more choosers (4) than choices (3), it couldn’t be permutations (permutations=no repetition, sequence doesn’t matter,like dealing cards from a deck). Number of different person/choice combinations is shamefully easy–3 to the power of 4. Emily’s question about how many different results, ignoring the person/choice pairing, is using combination theory. The answer then becomes (n+k-1)! divided by (k!(n-1)! where n is number of choices and k is number of choosers. That is then 6!/[4!*2!] which works out to 15.

By: Charlie

Charlie — Mon, 01 Jun 2009 17:15:00 +0000

Come on folks…I know it’s Monday morning but these comments don’t flow with those I’m used to seeing from Floss readers…basic math word problem. Lon = 3, Ron = 3, jon = 3, Don = 3. Multiply and get answer. Order doesn’t matter. :)

By: PartiallyDeflected

PartiallyDeflected — Mon, 01 Jun 2009 16:53:00 +0000

When I can’t remember which should be the exponent I just visualize a key.

If there are four pins, but only one possible position for each pin then there is only one totals combination 1**4. If one pin has four possible positions then 4**1. So it’s positions (menu items) to the pins (employees) power.

By: Sandy Wood

Sandy Wood — Mon, 01 Jun 2009 16:10:00 +0000

Nachos seem very popular at theatres today… I see lots of folks with them. Peanuts not so much, but they were common when I was growing up. (Granted, that was in Georgia, which is known for them.)

By: Suzanne

Suzanne — Mon, 01 Jun 2009 15:22:00 +0000

My husbands first response was:

ONE. Who eats peanuts or nachos at a movie?

He did then do the math and came up with the correct answer of 81.

By: Sandy Wood

Sandy Wood — Mon, 01 Jun 2009 13:46:00 +0000

I understand, Emily… I struggled with the phrasing to get the answer I desired, and actually meant to include both answers in the solution. I’ll go back and add that information.

Thanks!

By: Frank

Frank — Mon, 01 Jun 2009 13:38:00 +0000

I’m with Emily. It seems like the question, as worded, is looking for the number of combinations, irrespective of employee.

By: Phill

Phill — Mon, 01 Jun 2009 13:03:00 +0000

I never really thought about it before, but it seems that this can be easily calculated with powers.

(items)^(number of people)=combinations

In this case, 3^4=81

It consistently works with any values. Such as 2 people with 3 items (3^2=9), or 3 people with 2 items (2^3=8), or 8 people with 37 items (37^8=3512479453921).

By: Emily

Emily — Mon, 01 Jun 2009 12:32:00 +0000

The wording of the question is a bit confusing; I wasn’t sure if you were asking for the number of man-choice combinations, or for the number of combinations of responses (i.e. popcorn-peanuts-nachos-nachos, nachos-nachos-nachos-nachos, etc., disregarding who says what).