Open Challenge: There are 4 contestants in a race, and ties are allowed. How many different RACE RESULTS are there? Note that it is possible to have a 3-way or 4-way tie.
10?
No, but if you are going to participate in this, you should be prepared to show/present/describe in detail how you got your result.
When you say race result, does that mean 1 contestant winning is different than another contestant winning?
It means to figure out the total number of possible race results. Each race result will be unique. Yes, an A,B,C,D finish is obviously different from an A,C,B,D finish.
Also remember to account for 2-way, 3-way, 4-way ties.
AAAA AAAB AABA ABAA ABBA AABB AABC ABBB ACBC ACCB ABCC ACBD ADBC ADCB ACDB ABDC ABCD BAAA BAAB BABA BABB BABC BACC BACD Im just gonna go ahead and guess cuz my head hurts at the moment, but since the first set that I typed up there^ has 17, multiply that by 4 and you get 68. So is 68 the answer?
A couple of things... Why did you stop at 17? What is the significance of doing so? Also, if you multiply by 4 you risk overcounting.
Each race result must be unique so I can't agree with multiplying by 4
Also 68 is not the correct result, but nice try. :)
It's 8am here and Im just doin this so I dont do my art work:P
Havent slept yet lol
r there answer choices?
I smell factorials
This is an Open Challenge...no answer choices.
idk maybe 31?
If that were the case, people could just guess the correct answer.
Also @Yuba, if A represents the 1st driver, B represents, the 2nd driver, C represents the 3rd driver and D represents the 4th driver, then AAAA makes no sense.
If you want to represent a 4 way tie, you may have to come up with a more creative way to do so.
AAAA meant they all got first place = 4-way tie lol
Yes, but your approach is not consistent. If that's the case, what would BBBB represent?
A = First, B = Second lol
So there wouldnt have been a BBBB(:
ABCD <<<<these 4 letters can be arranged among themselves in 4! ways. now tie between 2 people, means there are actually 3 different entities, 2 individual and 1 group of 2, like (AB)CD , and they can be arranged in 3! ways. similarly, 3-way tie >>>>2! ways 4way tie>>>>1! way = 1 unique way. in all, 4!+3!+2!+1! ways.
^^^ Won't there be double accounting a few times?
@hartnn, another good try, but it is not the result @Yuba, I assure you that your approach is limited if you cannot introduce a way to represent each individual racer. You cannot use AAAA to represent 4 different racers.
yeah, not double counting, but i guess, i have missed many cases
like a 3-way tie, (ABC)D, D(ABC) there are many other cases for this , right?
for a 3 way tie, i think there r 8 cases, 2 with A, 2 with B, 2 with C,2 with D ....not sure i covered everything yet...
you realize this could go on and on and on, right? lol. this could take all night. :)
You can have 1 person win, or 2 persons win,..., or 4. The total number of ways for this is. $$ \Large{ \Sigma_1^4\binom{4}{n}\binom{3}{3-n}\\ } $$
@ybarrap, your approach considers "winners" only, but not the total number of race results. There's a huge difference I assure you.
There is also a negative there, impossible. ok
\(\large\binom{4}{n}\) is the number of ways to win, \(\large \binom{3}{4-n}\) is the number of ways for the others to lose: $$ \Large{ \Sigma_1^4\binom{4}{n}\binom{3}{4-n}\\ } $$
$$ \Large{ \Sigma_{n=1}^4\binom{4}{n}\binom{3}{4-n}\\ } $$ Where n = the number of winners, n -=1 means there is 1 winner, n=2 means there is a tie, with 2 winners,..., n=4 means there is a 4-way tie.
You have two groups, winners who may have tied and the rest. The winners could be any of the 4:\(\large \binom{4}{n}\). Once the winners are determined, there are (4-n)! ways that the remaining players can finish. Totals are: $$ \Large{ \Sigma_{n=1}^4\binom{4}{n}(4-n)!\\ } $$
@ybarrap, I think you are assuming a specific formula can be applied to this problem to solve it.
I'm actually trying to count the ways that players can place. If you have a tie with 2, you have something like: ww23 or 2w3w. Where "w" means win and 2 and 3 means 2nd and 3rd place.
So \(\binom{4}{1}\) counts things like, w234, 2w34, 23,w4. Those 2nd 3rd and 4the places can be any of 3! positions while wins can only be in 4 positions. So total for a single winner would be 4 \(\times\) 6 = 24.
thats just like arranging 4 people in 4 positions = 4! =24 ways
For ties with 2 winners, you have \(\binom{4}{2}\), with things like: ww23 or w2w3, etc. So there are 6 ways to have ties with 2 winners and 2! ways for the losers to place for a total of 6 \(\times\) 2=12.
@ybarrap , what are you getting for a 3 way tie ? and for a 2 way tie, there are much more than 12 ways....
For a 3-way ties, I get things like: www2 or w2ww, and 2www. So there are \(\large \binom{4}{3}=4\) ways for the winners and for losers, 1! ways for them to place, for a total of 4 \(\times\) 1=4.
there r 8 possibilities for a 3 way tie, (ABC)D , ABC coming 1st, D coming 2nd D(ABC), D coming 1st, ABC coming 2nd. A(BCD) (BCD)A B(ACD) (ACD)B C(ABD) (ABD)C
Hold on people, I'm here.
^like a boss
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