Official Quant thread for CAT 2013

hello plz tel me is it worth for fresher to apply for IIFT ?


rajeev planted some plants in his lawn but in a certain fixed pattern:

1)most of the rows have neither roses nor marigolds
2) there are two more rows of orchids than tulips and two more rows of roses than orchids
3) there are 4 more roses than tulips
4) there aren't as many rows of lily as fireball
5) there is one less marigold row than rose
6) there is one row of tulips
7) max no of rows he planted is 6

Q) How many fireballs he planted?
A) 2 B)6 C) 2 or 6 D)inadequate data

Explain the approach !!

😁

10% of auto drivers on Delhi Roads were penalised for not having proper documents last Sunday. 20% of the auto drivers who did not have proper documents escaped somehow. What percent of total auto drivers on Delhi Roads were not having proper documents last Sunday?


A. 10% B. 12.5% C. 30% D. 25%

Sum of five consecutive terms of an increasing geometric progression is 211. It is known that all the five terms are positive integers. Find the number of perfect squares among these five terms.


A. 2 B. 3 C. 4 D. 5


@amresh_maverick

In a 5 — 5 square grid composed of 25 units squares, there is a shaded unit square in fourth column and second row. How many rectangles are there in the grid which contain that shaded square?



A. 16 B. 32 C. 64 D. 128



@Dazed-Confused @JanardanJakad @amresh_maverick let me know if this is good mg

ravi can do a work in 2 days and if the same work is to be done by Rajesh, he requires 3 days. Ramesh can do a work in 5 days, while for the same work, Rajesh requires 4 days. All of them together finish a project in 20 days. If Ramesh wants to work alone, how many days will he require to complete the project?Options are - 30, 60 , 83, 66
Please explain in detail..

A CONTRACTOR EMPLOYED 30 MEN TO DO A PIECE OF WORK IN 38 DAYS. AFTER 25 DAYS, HE EMPLOYED 5 MEN MORE AND THE WORK FINISHED 1 DAY EARLIER. HOW MANY DAYS HE WOULD HAVE BEEN BEHIND, IF HE HAD NOT EMPLOYED ADDITIONAL MEN?

N = 2^33 * 3^21

How many positive divisions of N^2 are less than N but do not divide N ?

The sets Qp are defined as (p, p+1, p+2, p+3, p+4, p+5,p+6) where p=1,2,3,4,5,.....................100 How many of these sets contain a multiple of 11

62
63
64
65

please explain your answer with approach thanks

what is hexanumber E78 in radix 7?


embarrased..plz solve

mr. roy bought 10 hens for rs x67.92y, the first and the last digits were missing. what was the cost of each hen????

http://placement.freshersworld.com/placement-papers/Mu-Sigma/Placement-Paper-Whole-Testpaper-37759

see last question

3f(x+2)+4f(1/x+2)=4x,,,x not equal to (-2)........f(4)=??????😠😠

Hi All,

Need help on this.
@Dazed-Confused @chillfactor @scrabbler @ScareCrow28


(x+2)(x^2 -2x + 1) / (4 + 3x - x^2) >= 0

I solved it as below

==> (x+2)(x - 1)^2 / (x^2 - 3x -4) ==> (x+2)(x - 1)^2 / (x -4)(x + 1)

Considering the above equation number line should look like this

----[-ve]------(-2)----[+ve]----(-1)-------[-ve]--------(+1)----[+ve]--------(+4)------[-ve]--------

But its not like that ! Can anyone help me ?

Will the critical point, logic doesn't work here ???


x

@giyan

here is fastest way to solve most complicated problems of type ax+by=c requiring to find integral solutions

Say we take a complicated example like 32x + 53y = 109...........(i) [try solving using conventional method and I can assure that it will take you hours]

Here is the method that I present [it might be known to some of you]

Master rule: pick up the smaller coefficient and divide other numbers by this, and replace other number by the remainders obtained after dividing.

In the example taken 32 is the smaller of the (53,32) so divide other numbers by 32 and replace them with the remainder to get

32x+21y=13 ..............(ii) [ when 53 is divided by 32 remainder = 21, when 109 is divided by 32 remainder is 13]

now the smaller of (32,21) is 21 ...so divide everything else by 21 and replace by remainders to get
11x+21y=13.......(iii)

Now we divide by 11
11x+10y = 2.....(iv)

Now divide by 10 to get

x+10y = 2.............(v)

Stop once the co-efficient of any of the variable becomes 1 or -1 stop]

Now back track


one variable for which coefficient is not 1, equate that variable = 1 and solve for other.

In eqn (v) co-efficient of y is 10 hence we put y =1 and solve for x


put y = 1 in (v) to get x= -8

[eqn (v) is done now ...so move to (iv) now]

€‹ €‹put x= -8 in (iv) to get y = 9


similarly back track upto original equation

put y=9 in (iii) to get x = -16
put x=-16 in (ii) to get y = 25
finally put y = 25 to get x = -38

So get the generalized solution as x= (53k-38); y = (-32k+25) [ as explained in my previous post]

Now if you would observe that the method described above is very simple and repetitive in nature and using this method you can get solution to any problem of type ax + by = c however complicated it may be within less than 90 secs in most of the cases. The answer comes even fast if you use -ve remainders



Now try 11x+ 19y = 70 using the method just learnt

Solution

11x-3y=4.....(ii) [ after dividing by 11]
=> -x-3y=1.....(iii) [after dividing by 3]

in (iii) put y =1 to get x=-4
put x = -4 in (ii) and y=-16
put y = -16 in original eqn to get x= 34

hence genralised solution is given by x = 19k+34 and y = -11k-16.

ATDH.




How many three digits integers have their hundred, ten and units digit in ascending order?

70
77
84
504

guys please share your approach thanks in advance

hey guys i'm a decent student but i am getting terrible marks in the AIMCATS haven't crossed 50 yet. any tips?

Radian

Two pipes A and B can fill an empty water tank in 40 and 50 minutes. An outlet pipe C can empty the full tank in 30 minutes. The tank is empty and A and B are opened simultaneously and after 10 minutes C is also opened. How long does it take to fill the tank in minutes?

55 1/2
57 1/7
55
NOT

guys please share the approach thanks in advance

A natural number has only two prime factors. It is 100 times the number of its factors. Find the sum of the digits of the least number satisfying these conditions

1
4
3
2

Please share the approach thanks in advance