Official Quant thread for CAT 2013

MBA CAT 2024
4561
@maddy2807 said:
In the middle of a circular park of radius 2r units, a circular hole of radius r units has been dug. The mud extracted from the hole has been spread uniformly over one third of the rest of the park, to make an elevated platform around the hole. This has led to an increase of 5 units in initial depth of the hole. Find the percentage increase in depth of the hole. A. 100% B. 200% C. 66.66% D. 33.33% E. None of these
a?
4562
@Ibanez said:
A ?
kaise kiya :splat:
4563
@Ibanez said:
A ?
approach batao
4564
@maddy2807 said:
kuch solution nikala. ya fir aaj b chod de?
chor dete hain ab to culdip , varun , chill saar hi help kar sakte hain isme
4565
@maddy2807 said:
A cyclic quadrilateral of maximum area is drawn inside a circle and is painted blue. Find the percentage of area not painted.A. 36.36% B. 44.44% C. 57.14% D. 48.13 %
A. ?
4566

my soln ..

20C2-25-10/20C2 = 155/190 = 31/38

4567
@maddy2807 said:
@catter2011 bhai tu to mere peeche hi padh jata hai ...
(10c2+10c2+2*d(5)+10c2-2*5c2)/190
=(135+52-20)/190
=167/190

ps - not open for discussion, lets forget this mixed party :p
4568
@maddy2807 said:
approach batao
cl nmat mock Q hai na.....mere ko ans yaad tha..but solution nahi aata..
4569
@gs4890 said:
kaise kiya
@maddy2807 said:
approach batao
Mentally kia hai abhi paper nahi hai

I took R as 1. so 2R= 2

Area of the ground = 4pi
Area of hole = pi

remaining area = 3pi.
1/3rd of this = pi
now, in pi area we are elevating by 5 units so volume = 5pi

This volume of mud was taken out of the initial hole so that means its depth would have been 5pi / area of hole = 5pi/pi = 5 units.

initial =5 and we increase by 5 units more so 100%
4570
@Ibanez but no where it is said the platform is of 5 unit height.
4571
@mailtoankit said:
cl nmat mock Q hai na.....mere ko ans yaad tha..but solution nahi aata..
complete ur homewrk...
4572
@maddy2807 yes sir..
4573
@maddy2807 said:
@Ibanez but no where it is said the platform is of 5 unit height.
It says "this has led to an increase of 5units in the initial depth of the hole" This just means that we elevated by 5 units. (The original hole hasn't been disturbed we just made it deeper by elevating mud around it"
4574
@maddy2807 said:
In the middle of a circular park of radius 2r units, a circular hole of radius r units has been dug. The mud extracted from the hole has been spread uniformly over one third of the rest of the park, to make an elevated platform around the hole. This has led to an increase of 5 units in initial depth of the hole. Find the percentage increase in depth of the hole. A. 100% B. 200% C. 66.66% D. 33.33% E. None of these
let height be h

pi*r^2*h=(4r^2*pi-r^2*pi)/3*5
=>h=5

so % increase = 5/5*100=100%
4575
@maddy2807 said:
In a party, 5 Indian couples and 5 American Couples meet and shake hands with each other. Find the probability that no wife shakes hand with her own husband and no Indian wife shakes hand with an American husband.A. 13/18B. 65/76C. 27/38D. 13/15E. 65/77
Total handshakes = 20C2 = 190

Restricted handshakes = Indian wives & American husbands(A)+Each wife with own husband(B)

A = 5*5 = 25
B = 10

Probability = (190-35)/190 = 31/38 :splat:
4576
@soham2208 u r making the same mistake as we did
4577
@Ibanez said:
It says "this has led to an increase of 5units in the initial depth of the hole" This just means that we elevated by 5 units. (The original hole hasn't been disturbed we just made it deeper by elevating mud around it"
bahut confusing statement hai...still it is correct.
4578
The difference between compound interest and simple interest for 3 years at the rate of 5% per annum is Rs. 61. What is the principal amount?

A. Rs. 9,000
B. Rs. 8,000
C. Rs. 7,000
D. Rs. 6,000
E. Rs. 5,000
4579
@krum said:
root2/2
man u r ryt OA is root2/2.......at least ab to approach batade yaar..
btw kya kya karna padta hai aapse approach jaanane k liye......
4580
@maddy2807 What is that mistake ? There is no double counting here I think :splat: