# @sumitgoel87

##### sumit goel 449 karma
###### XAT, SNAP, CMAT & OthersNMAT 2012-Relevant Questions Discussion
There are three classes X,Y and Z. Average of class X is 83. Average of Class Y is 76. Average of class Z is 85. Average of class X and Y is 79, average of class Y and Z is 81. Find average of three Classes.
a.81 b.81.5 c.82 d.84

though i dont think its the right place to reply...u can use quant thread for these type of queries....

btw my take goes like this
X: 83
Y: 76
Z: 85
X+Y: 79
Y+Z: 81

ths imples n(X):n(Y) = 3:4
n(Y):n(Z) = 4:5

therefore aggregate of three classes will be:
= 3(83)+4(76)+5(85)/ 3+4+5
= 81.5 plz check out.
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###### CATOfficial Quant Thread for CAT 2011 [Part 8]
tarun g Says
can someone explain the logic behind this question?

M1,M2,M3,M4,M5,F1,F2,F3,F4,F5

A couple can be chosen in 5C1 way the left people will be arranged
8*6*5*4*3*2*1*1
Therefore 5760*5*2*9

but i am not sure...so wnt some one to check
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###### CATOfficial Quant Thread for CAT 2011 [Part 8]
i am getting 1/1016 ...OA kehta hai pi/2040......

obvious it will be OA....i hav rechecked and sorry to say pie cant come in answer. as its asking for ratio...i have wrongly put pie in my previous post
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###### CATOfficial Quant Thread for CAT 2011 [Part 8]
consider a circle with unit radius. There are 7 adjacent sectors in it s1....s7 such that there total area is 1/8 of the area of the circle. The area of the j th sector is twice that of the j-1 th sector for j = 2,3,4..7. Find the ratio of s1 to the circle.

1/8*127 = 1/1016 ??
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###### CATOfficial Quant Thread for CAT 2011 [Part 7]
If there are 209 students..
P says 133 are females.
Q says 132 are females.
Clearly, Q is a female.

If there are 209*2 students, P would say there are 266 females and Q would say there are 264. Clearly, this data is inconsistent.
So, I and III are correct.

@N(P+K) bhais: abhi shikayat karta hoon Chill sir se

bhai, class mates means excluding the speaker so the students will be 209+1=210students....rest u r right...but OA will becum wrong
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###### CATOfficial Quant Thread for CAT 2011 [Part 7]
Two classmates P and Q have a conversation as below.
P: 7/11 of my classmates are females.
Q: That is interesting, because 12/19 of my classmates are females.

Assuming that both P and Q speak the truth, which of the following statements are true?
I. Q is a female.
II. P is a female.
III. There are a total of 209 students in the class.

(1) Only II and III
(2) Only I
(3) Only I and III
(4) None of the statements are true.

noblekalra Says
only I and III my take....

OA should be (2) Only 1......want my approach??
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###### CATOfficial Quant Thread for CAT 2011 [Part 7]
A father is aged three times more than his son Ronit. After 8 years, he would be two and a half times of Ronit's age. After further 8 years, how many times would he be of Ronit's age ?
a). 2 times
b). 5/2 times
c). 11/4 times
d). 3 times

F = R + 3R
(F+ = 2.5(R+

frm this u can find out the solution
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###### CATOfficial Quant Thread for CAT 2011 [Part 7]
7-a+7-b+7-c+7-d=21
a+b+c+d=7
10C3 ways

it is saying less then 7 in every case, so dont u thnk we should take max as 6 and OA becum 6C3 = 20.
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###### CATOfficial Quant Thread for CAT 2011 [Part 7]
There are 4 subjects namely a,b,c,d in an examination. In how many ways, a student can score a total of exactly 21 where all the individual subject scores are below 7?

20 aa raha hai bhai mera to.....
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###### CATOfficial Quant Thread for CAT 2011 [Part 7]
Q. No. of integral solution of x + |y| + z = 10 ??

1. 402
2. 304
3. 202
4. 502

1. 402, whats d OA?
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