ds 3

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ds 3

by resilient » Mon Jun 23, 2008 8:24 pm
i was stuck on the wording here. The question asks for the YOUNGEST but statement 2 explains of the younger 2. This cant technically explain of the the youngest.

qa is b
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by codesnooker » Wed Jun 25, 2008 1:15 am
It is actually very simple question but trick is hidden in its text. So lets try to solve this interesting puzzle.

From the question stem we know that,

Sum of Money = $ 200,000 = M
Number of beneficiaries = 4

Who are the beneficiaries?
Ans: One Spouse, and three childern

Lets assign the variables to these people.

Spouse = S
(Children in decreasing order of their age)
1st Child = Fc
2nd Child = Sc
3rd Child = Tc


So,

S + Fc + Sc + Tc = 200,000

Now let's take condition (1).


S = M/2 = $ 100,000
Fc = (1/4) (M/2) = M/8 = $ 12,500


Now the remaining money should be divided between Sc and Tc. But there is no condition provided how it should be divided among them. So, we can't say how much Tc is going to get.

Hence Statement (1), INSUFFICIENT.

I hope till now it must be clear to you why your selected answer is wrong.

Now let's concentrate on statement (2):

It states that two younger children (that is: Sc + Tc) receives $12,500 more than Fc.

Sc + Tc = Fc + 12,500

AND

It also states that the two younger children receives $62,500 less than spouse.

Sc + Tc = S - 62,500

Now as we know that, S + Fc + Sc + Tc = 200,000

Now as there are 4 variables in the above equation and both Fc and S are in a equal relation to Sc and Tc, so it means that both Sc and Tc going to share the equal amount of money. I know, its bit difficult to understand this concept, but this is the fact and you need to digest it.

So lets consider, Sc = Y. Therefore, Tc = Y
Hence,

2Y = Fc + 12500 ----> Equation 1

and
2Y = S - 62500 ----> Equation 2
and also,
2Y + S + Fc = 200000 ----> Equation 3

Now add equation 1 and equation 2,

4Y = S + Fc - 50000

It means, S + Fc = 4Y + 50000

Place the value in equation 3,

2Y + 4Y + 50000 = 200000


Now from here you can easily compute the value of Y (that is the youngest child's share).

Hence Statement (2) is alone SUFFICIENT.

Hope this helps...

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by niraj_a » Wed Jun 25, 2008 5:31 am
codesnooker,

B is what I chose too, and your explanation makes sense. BUT, from the poster's screenshot it looks like the OA is A.

what gives?

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no

by resilient » Wed Jun 25, 2008 7:53 am
no no i just guessed on choice a. its wrong and very obviously but still trying to reason out of choice b. Equations are great if you are wired that way, but Im a mapper and map information out and reason my way out. Its a preference issue.
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by niraj_a » Wed Jun 25, 2008 9:36 am
oh ok, so B is right..cool

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Re: no

by codesnooker » Wed Jun 25, 2008 11:08 pm
resilient wrote:no no i just guessed on choice a. its wrong and very obviously but still trying to reason out of choice b. Equations are great if you are wired that way, but Im a mapper and map information out and reason my way out. Its a preference issue.
Actually Resilient, there is no need to solve the question. I just wired it into equation so that one who reads can easily comprehend the solution. In real world, I don't even touch pen for the DS questions and still my hit ratio is more than 90%. Frankly speaking it saves my 50% of time by applying this approach.

You can also solve this even in your mind.

HOW?

Lets conclude in our mind, what information do we have:-

1. We have 4 people who are going to get money.
2. We know total money.
3. We know the relation of two younger children with first child and spouse.
4. Both younger child have equal relations with other two dependent members.

Hence, we can conclude that they will share equal amount of money and now we know the relation also between each member, hence we can derive the money for the youngest child.

It's done and I will just hit the answer, rather than picking up the pen and jotting down the information. I feel to do it with CR approach rather than following it as a PS question.

However, it depends upon personal preference.