@hanushanand said:mera WWB me 32*25*18/2 aa rha hai! and BWW me same.. 32*24*18/2 .. Don't know where I am getting it wrong! Verify!
Yahi to doubt hai :banghead:
@ankita14 said:For example, bww ke liye.. 32 black squares to choose from, then you can't choose the 8 white squares that lie in the same row or column as the black one, so 24 white squares left, then I can't choose 6 white squares so 18, but the two white squares are interchangeable so divided by two. 32*24*18/2=6912
:mg:
@hanushanand said:mera WWB me 32*25*18/2 aa rha hai! and BWW me same.. 32*24*18/2 .. Don't know where I am getting it wrong! Verify!
32*25*16/2 par.
@ankita14 said:Yahi to doubt hai
hehe.. Doubt kya hai.. alag hi aata hoga then.. ab BWW aur WWB me diffy to hai naa.. so diffy answer bhi aayega.. ! I guess!
@hanushanand said:hehe.. Doubt kya hai.. alag hi aata hoga then.. ab BWW aur WWB me diffy to hai naa.. so diffy answer bhi aayega.. ! I guess!
question me order nahi diya na uncle to kaun sa lenge :P
@hanushanand said:hehe.. Doubt kya hai.. alag hi aata hoga then.. ab BWW aur WWB me diffy to hai naa.. so diffy answer bhi aayega.. ! I guess!
😲 the question is the same. To select 2white squares and 1 black 
@ankita14 said:32*25*16/2 par.
I think number of ways will always go with max possible cases
say you choose first white in 32 ways , second can be choose in 25 ways . to avoid repetition , we divide by 2!
so in total 400 ways
now we have 64 - 8 - 8 - 6 - 6 = 36 squares left of which 18 are black
so 400 * 18 = 7200 IMO
say you choose first white in 32 ways , second can be choose in 25 ways . to avoid repetition , we divide by 2!
so in total 400 ways
now we have 64 - 8 - 8 - 6 - 6 = 36 squares left of which 18 are black
so 400 * 18 = 7200 IMO
@naga25french said:I think number of ways will always go with max possible casessay you choose first white in 32 , second can be choose in 25 ways . to avoid repetition , we divide by 2!so in total 400 waysnow we have 64 - 8 - 8 - 6 - 6 = 36 square left of which 18 is blackso 400 * 18 = 7200 IMO
It'll be 16. Not 18. Diagram wise. But anyway both 6400 and 7200 are incorrect. Why does the ans change on changing the order? (Wwb and bww)
@iimnehajain said:@ankita14 @hanushanand isnt this a question of combination n not permutation?
Yea, so we are dividing by 2 to take care of that.
@naga25french said:I think number of ways will always go with max possible casessay you choose first white in 32 ways , second can be choose in 25 ways . to avoid repetition , we divide by 2!so in total 400 waysnow we have 64 - 8 - 8 - 6 - 6 = 36 squares left of which 18 are blackso 400 * 18 = 7200 IMO
@ankita14 said:It'll be 16. Not 18. Diagram wise. But anyway both 6400 and 7200 are incorrect. Why does the ans change on changing the order? (Wwb and bww)
wats goin on ??
@ankita14 said:It'll be 16. Not 18. Diagram wise. But anyway both 6400 and 7200 are incorrect. Why does the ans change on changing the order? (Wwb and bww)
@naga25french said:I think number of ways will always go with max possible casessay you choose first white in 32 ways , second can be choose in 25 ways . to avoid repetition , we divide by 2!so in total 400 waysnow we have 64 - 8 - 8 - 6 - 6 = 36 squares left of which 18 are blackso 400 * 18 = 7200 IMO
@hanushanand said:Kiska??
maybe time missed a trick here....order is changing the answer and it will be 6400 mostly
@Vascent said:@YouMadFellowWhere have you disappeared sir jee?
Well, long story.. I left for gym at 5:00 pm.. Car's tyre got flat.. I moved it to repair shop.. Wasted 1 hour there.. then went to gym.. and now I am back.. eating maggi after a nice bath and tight biceps :splat:
@ankita14 said:It'll be 16. Not 18. Diagram wise. But anyway both 6400 and 7200 are incorrect. Why does the ans change on changing the order? (Wwb and bww)
The answer is in the mistake i did .. 18 and 16 confusion is main thing for variation .. As i said , number of ways should be calculated for the case which produces max number of solution .. in this question , it would be WBW which is 6912
@ankita14 said:@fisherking Number of ways to select two white squares and one black square such that no two lie in the same column or row? Isme bww ya wbw karke karne se ans aa raha hai lekin wwb se galat ans aa raha hai
32*25*18/2 = 7200