Grouping / Speed comparison concept: 25 horses; min races to find fastest 3 horses

Рет қаралды 19,456

11 жыл бұрын

25 horses for race; minimum races needed to find the fastest three. Max 5 horses can run at a time and we cant record their timings.

Пікірлер: 34

@balaji.r788 8 жыл бұрын

Thanks so much for your explanation!

@vivekrawatvlogs 8 жыл бұрын

Excellent Explanation :-)

@thegauravmaths 8 жыл бұрын

+vivek rawat Thanks!

@heratpatel7174 7 жыл бұрын

Thanks sir for such a great explanation...

@thegauravmaths 7 жыл бұрын

Thanks Herat Patel!

@ridhijoshi3674 10 жыл бұрын

Thanks so much for your explanation.This was asked to me by an investment bank.

@thegauravmaths 10 жыл бұрын

Thanks Ridhi! i wish you success!

@saumyojitdas4212 4 жыл бұрын

in the last race (7th) we are taking 2,3,6,7,11 for a race . but we know that 3 lags behind 2 and on the otherside 7 lags behind 6 . Why we are competing 3 and 2 & 6 and 7 again in 7 th race. INstead we should compete 2 and 6 in 7 th race out of which winner will be 2nd in entire group and for 3rd 6,7,11 in 8th race

@thegauravmaths 4 жыл бұрын

hello the question is to minimise the number of races; so why do u want to go to 8th race when we can get the top 3 in 7 races?

@biswashreepanda3948 5 жыл бұрын

Sir ,plz explain me ....why 4th and 5th position of race 5 can't b better than 2nd and 3rd of race 1......in race 5 they were slower than the 1st,2nd,3rd of race 5....they could b faster than 2nd,3rd of race 1....u didnt make a fair competition...plz explain

@thegauravmaths 5 жыл бұрын

you are right..they can be better...but..our purpose is to find the top 3; the 4th and 5th of any race will certainly be eliminated as we are sure they cannot come in top 3 positions. the other horses will remain in contention till last race.

@kriishm5158 4 жыл бұрын

Sir how to find fastest horse in 6th and 8th race

@monikasingla9887 6 жыл бұрын

thank you sir

@thegauravmaths 6 жыл бұрын

thanks!!

@chakki9293 4 жыл бұрын

Without knowing there timing at particular distance what they have clocked, how can you judge 3 fastest horses from 25..for me the explanation looks funny

@ksnayadi 5 жыл бұрын

The explanation is flawed because the 4th horse in the first group for example can be faster than the first horse in the second group so you cannot really eliminate the 4th and 5th positions in any group. Think hard and you will realize that the explanation does not fully satisfy the problem.

@thegauravmaths 5 жыл бұрын

hello....yes the 4th horse can be faster than the 6th horse, but we dont want to rank all the 25 horses, we just want to find the top 3; so the moment we are sure that any horse is not in the top 3 we will eliminate it; thus if you look at horse number 4 it is certainly worse than the first three horses and thus though it might be faster than horse number 6, we will eliminate it. We are just suppose to find the top 3 horses to satisfy the question..... Hope it helps.... thanks!

@balaji.r788 8 жыл бұрын

I just want a clarification on 'how he eliminates 8th horse ' ?

@thegauravmaths 8 жыл бұрын

hello..See..the 8th horse is coming 3rd in his group; Now the horse number 6 who is the winner in this group is coming 2nd when all the group toppers were running which means that at best the horse number 6 will be the runner up in all the horses( he might not be the runner as well...but we are taking the best case) and therefore the best case for horse number 8 is that it will be 4th position(horse number 7 is 3rd) and so we can eliminate the 8th horse as we are interested in finding the top 3 positions. The moment we are sure that some horse is outside of top 3, we will eliminate it. Hope it helps...Thanks!

@bipinkumar-cm4ou 7 жыл бұрын

thank sir

@thegauravmaths 7 жыл бұрын

thank u!

@rashmiyadav3186 5 жыл бұрын

Sir why you use 7th rank? In all 5th rank get 1-1 horse as a toper so we getting top 5horses in all rank then we take 6th rank for all these 5topper horses and simpley say in these 6th rank top 3 horses are the topper.. Please let me why use 7th rank??

@thegauravmaths 5 жыл бұрын

yes....i clearly mentioned in the video too...if you take just 5 races and then select the toppers, you are not taking into account the runner up horse in the original group of the topper; he can be better than the runner up among the group toppers.

@Chander1810 10 жыл бұрын

Sir, Why can't 4th horse be faster than the 6th horse....?? That is 4th horse is 4th in 1st grp but it might be that he runs faster than 6th one...

@thegauravmaths 10 жыл бұрын

hello Chander. yes,, u r right. 4th horse cud be faster than the 6th..but..it is definitely not in the top 3..the moment we know that fact, we eliminate those horses as the question is to find top 3...horse num 6 remains in contention for top 3 till the last step; it might happen that top 3 comes as 1,2,3 only and 4th and 5th also as 4 and 5...but our objective is to limit ourselves in finding top 3. hope u got...

@Chander1810 10 жыл бұрын

Gaurav Bakliwal Yes sir, got it.Thank you so much sir for the explanation.

@suhaspartha342 8 жыл бұрын

didnt get u. assume 1st five horses has speed range of 60-65units. 2nd 5 horses has speed range of 50-55units. therefore the 4th horse can obviously b faster than 6th one right???

@thegauravmaths 8 жыл бұрын

hello. Yes the 4 th horse can be faster than the 6th horse....but our objective is to find the top 3 horses; the moment we are sure that some horse is not coming in top3 we are eliminating that horse; so the 6th horse will remain in contention for the top 3 slots till the last race, it can happen that the horse num 1 2 3 are the top 3 horses and horse num 6 might be less than horse num 4 and so the horse num 6 will be eliminated in the last race; we are anycase interested in fastes 3 horses. hope it helps...thanks!

@mahesh9762132636 5 жыл бұрын

Gaurav ... 4th Horse can be faster than 6th horse and hence striking 4th and 5th column doesnt make any sense....

@thegauravmaths 5 жыл бұрын

@mahesh9762132636 5 жыл бұрын

@@thegauravmaths Gaurav bhai thoda samzo ...as per your assumption you are striking every 4 th and 5th of their respective group ...and yes 4th would be worse than top 3 of its respective group so in that case those top 3 would be winner in first race only...we have to take all the possibilities you can't just make injustice to 4th and 5th of every group

@thegauravmaths 5 жыл бұрын

See..we need to find the top 3 from the whole lot; so the moment any horse is coming 4th or 5th in any race, it should be eliminated. After every race of the 5 groups, we can manually retain the top3 in each group and eliminate 4th and 5th from each of those groups. thanks...

@shyamprasad7362 6 жыл бұрын

Ok mr sir ..now I got it ... But I am gona apologies no fucking body ... Becoz it's a public platform which comprises all kinds of people like me also ... My may of conveying msg like this only .. anyway thanks for enlighting me .. peace

@thegauravmaths 6 жыл бұрын

i m happy you got it..thanks! all the best !