Official Quant thread for CAT 2013

@bodhi_vriksha said:
Yet to receive the right answer Team BV--Pratik Gauri
Isn't it 11/24? :o

regards
scrabbler


@bodhi_vriksha said:
Estallar12 draws a square PQRS of side 1 unit. He then draws 10 straight lines
is it 11/2
@Koushik98 said:
Triangle ABC has unit area. P, Q, R divides the three sides in the ratios as shown in figure. Find the shaded area of triangle.
sir is it 15/32
@scrabbler said:
Isn't it 11/24? regardsscrabbler
no 😞 try again .. seems u r commiting a v small mistake .. close yet so far :P

Team BV--Pratik Gauri
@bodhi_vriksha said:
Yet to receive the right answer Team BV--Pratik Gauri
is it 7/8??
@Koushik98 said:
is it 7/8??
no.. How can the area be so large koushik98? You have made the shaded area> 1/2 .. Think again is this poss?

Team BV--Pratik Gauri
@bodhi_vriksha said:
no.. How can the area be so large koushik98? You have made the shaded area> 1/2 .. Think again is this poss?Team BV--Pratik Gauri
15/4 ?

@rnishant231 said:
15/4 ?
nishant .. area of triangle is 1 ... shaded area which is a part of triangle acc to u is approx 4 😛 Try again :(

Team BV--Pratik Gauri
@bodhi_vriksha said:
This one is a BV problem Try it folks Team BV--Pratik Gauri
3/8 ??
@bodhi_vriksha jee kindly upload the images to www.postimage.org

and paste the link of the image here, it is difficult to see the image while solving. the image will get embeded.
@bodhi_vriksha said:
Yet to receive the right answer Team BV--Pratik Gauri
0.45??
@albiesriram said:
0.45??
BANG ON !!!!!!! :)
Share your approach ..

HINT to other puys : Use mass geometry :)

Team BV--Pratik Gauri

is it by any chance 1/8?

@bodhi_vriksha said:
no try again .. seems u r commiting a v small mistake .. close yet so far Team BV--Pratik Gauri
Sir getting 11/24 only :(
@bodhi_vriksha said:
BANG ON !!!!!!! Share your approach .. HINT to other puys : Use mass geometry Team BV--Pratik Gauri
11/24 ? pls check the attachment
@ScareCrow28 said:
Sir getting 11/24 only
11/24=.4583 which is a fraction greater than .45 .. so u may have got +3 .. :)
but the motive of this question was to get the approach correct ..
Act i am out ..so wont be able to upload the figure but i solve these kind of prob by mass geometry...
as AQ is median .. ar(aqc)=1/2...
now using mass geometry ,
put weights of x at B and C .. hence weight at Q will be 2x .
as AP:PC=1:3 --> weight at c=x .. so weight at A will be 3x .. SO wight at R=4X..
similarly, weights at A=3x and at Q=2x... so AO:OQ=2:3(inverse ratios of weights)..

now ar(aor)/ar(aqc)= 2*1/5*4=1/10
ar(aor)=1/10*1/2=1/20 =0.05 .. hence ar(ORCQ)=0.5 - 0.05= 0.45 :)
Team BV--Pratik Gauri
@bodhi_vriksha said:
BANG ON !!!!!!! Share your approach .. HINT to other puys : Use mass geometry Team BV--Pratik Gauri
sir the same mass point geometry used by me . kept weights as 2,2,4 at P,Q,R respectively. found out the ratio of PR and AQ. PO:OR is 2:1 , and AO : OQ is 2: 3 respectively. ( I solved it in FB itself. .)
@albiesriram said:
sir the same mass point geometry used by me . kept weights as 2,2,4 at P,Q,R respectively. found out the ratio of PR and AQ. POR is 2:1 , and AO : OQ is 2: 3 respectively. ( I solved it in FB itself. .)
@bodhi_vriksha @albiesriram Alien to this concept..any link where i can find mass geometry info ?
@albiesriram said:
sir the same mass point geometry used by me . kept weights as 2,2,4 at P,Q,R respectively. found out the ratio of PR and AQ. POR is 2:1 , and AO : OQ is 2: 3 respectively. ( I solved it in FB itself. .)
good sriram :)
@rnishant231 said:
@bodhi_vriksha@albiesriram Alien to this concept..any link where i can find mass geometry info ?
i am out right now .. would try to upload the whole funda by tonight if possible :)

Team BV--Pratik Gauri
@bodhi_vriksha said:
good sriram i am out right now .. would try to upload the whole funda by tonight if possible Team BV--Pratik Gauri
Thanks..