CAT 2008: Quantitative Questions a Day 1 to 50 - The discussions

[financemadkp]

Tricky question.....Heres my take


Container Volumes: A & B
Initial Spirit Volumes: V1 & V2
Spirit Concentration: p & q

so ....
(p*(B-V1) + V2*q)/B = q+5

(p-q)*(B-V2)=B*5

conditions
(x): V2>V1
(y): p-q= A/(A-V1)*10


Now Both these conditions satisfy the question independently.

So my ans is option:3
CAn be answered by either X or Y

[shanky_2k8]

Originally Posted by r_mondkar

i dont think it matters bcos the ratio i.e. the conc is same in both whole A as well as any amount from A

i hope i am right

u r right here but what u hav done in ur solution is not right....
i m reiterating the fact that it holds true only if whole of the content of A is transferred to B to make B full... which is not the case given here....and so u can't assume things like that

hope i m clear

[Aarav]

Originally Posted by arbit_rageur

Should correct the first line to answer is (3)-either statement can be used...dint read the options corectly

As we can all see, the asked question can be answered using the statement in the question only and we don't really require (X) and (Y) here.

Mark the strongest possible option which in our case is (5) -> because if (3) is correct then so is (4) according to the language of the options.

[deepthi_818]

Even without using any statement i get the equation-

Let a=conc of A, Va=initial vol of A, Ta=capacity of A
b=conc of B,Vb=initial vol of B, Ta=capacity of B
From the given condition.. final conc of B would be
[(Tb-Vb)*a+Vb*b]/Tb

Conc inc by 5%

[(Tb-Vb)*a+Vb*b]/Tb - b=5;
Result is (a-b)*[1-(Vb/Tb)]=5 Vb/Tb will be less than 1,

Therefore [1-(Vb/Tb)]<1 implies a-b>5, for this neither X or Y is required... So i am confused, which option to go for... Please help me if i have gone wrong in my approach

[isha_pisces26]

Let the two volumes be V1 and V2
conc x and y
initial volumes a and b
in containers A and B respectively.

We add (V2-b) volume of x conc into B
now concentration in B is
[ ( ( (y*b)/100) + ( ((V2-b)*x)/100) ) ]/ V2 = (y+5)/100

=>by + V2*x – bx = V2*y + 5*V2
=>b(x-y) = V2(x-y-5)
=>b = V2 ( 1 - 5/(x-y) )

Now, since b and V2 are volumes, they both have to be positive
=>1 – 5/(x-y) also has to be positive
=>1 – 5/(x-y) > 0
=>1 > 5/(x-y)
=>|x-y| > 5

Thus we need neither of the two conditions to derive the answer.
Hence the option is (5)

[deepakraam]

Jus worked out like this and I'm getting the ans as option (5)

A=5l with 60% concentration.So s(a) = 3l (litres).
B=10l with only 5 litres full with 50% concentration.So,s(b)= 2.5l.

Now after pouring A into B,s(b) = 5.5 with 55% concentration.But none of the statements is useful for me in this case.

Is the ans for the above q option 5?

-Deepak.

[shivam_01]

hey guys lot of different answers coming up
Aarav can u tell us what is the answer and correct approach too

[kk_sonam]

i guess i mm too late... n cuming up wid d same ans..

option 5..

n already so many explanations are present.. dont feel lyke writing everything again

[kk_sonam]

can anyone plz temme when is the question posted in this thread

[atombomb_blast]

Hi could some one help me in solving this

1) The digits of a three-digit number A are written in the reverse order to form another three-digit number B. If B > A and B−A is perfectly divisible by 7, then which of the following is necessarily true?

a) 118<A<317
b) 100<A<299
c) 106<A<305
d) 112<A<311


2 )What is the value of n such that n! = 3! * 5! * 7!

3) What is the remainder when 484! is divided by 25? how to solve this kinda prob...i forgot the exact question jus to know how to solve these kinda probs....