Ambiguity in Mathematics Section of Qualifier [Afternoon Shift]

[Pankaj Srivastava]

Hello Online Degree Team,

As advised, I am sharing my query on Discussion Forum.

There was this question in which Salaries and Increments of employees of a company were given, and candidates were expected to calculate the overall expenditure of the company in 2020. The issue with this question was that it was not mentioned in the question whether the Increment was Simple Interest or Compound Interest i.e. whether Increment is to be calculated only on the 2010 salary figure for each year or also on the Increment of each subsequent year till 2020. Without this important piece of information, it was not possible to calculate the right answer. 

Lot of candidates wasted much time on this question which was impossible to solve because of lack of complete information. Due to this reason, I think that IITM  should award full marks to all the candidates who received this question in Mathematics in their Question Paper Set. 

Sincerely,

[Geetaanjali GNS]

This question was in shift 1, right?

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[Renjith K S]

one more Is zero a multipe of 3?

[Kaushal Patil]

Hi, 

I completely agree with your argument and many students( me being one of them) have wasted lots of time on this question due to lack of information. 

But when I looked at they options of this question, it can be seen that all the options have varying y intercept term. Now in context to the question the y intercept is the value of expenditure at zero years from that year or it also means that it is the value of expenditure at the given year. Now we were given the initial salaries/salaries of all employees at that given year. 

So indirectly we were given the value of y intercept which is no thing but the addition of all the salaries at the initial year. 

Hope it helps  

[Pankaj Srivastava]

Yes. The following link would be quite useful for the purpose of understanding how zero is a multiple of 3: https://www.expii.com/t/multiples-definition-examples-9031#

On Tuesday, December 1, 2020 at 9:08:00 AM UTC+5:30 Renjith K S wrote:

[Pankaj Srivastava]

Dear Kaushal,

Thanks for your reply but that is not the way to solve a mathematics question i.e. by way of looking at options or answers.  My question is: Will a mathematician, even a PhD, would be able to solve that question without complete information? The answer might be "YES". He would come out with two solutions: One with the assumption of Simple Interest and the other with the assumption of Compound Interest. That makes this question ambiguous. Isn't it?

[Kaushal Patil]

Yes, definitely agree that there exists ambiguity in the question due to lack of information. 

[Siddharth Singh]

If nothing is mentioned then it means Simple Interest.

[Pankaj Srivastava]

Really?? Who told you??

[Kaushik Deka]

Hello Mr. Srivastava,

We know that compound interest grows exponentially, while simple interest grows linearly. As far as I recall, there was no information in the question that implied an exponential growth, so I solved the problem assuming linear growth i.e. SI payouts as linear equations. Though you have raised a valid practical point, the law of parsimony / Occam's Razor - a problem-solving principle in the physical sciences - states that the simplest solution, i.e. a solution that is not complicated by unspecified variables, is the right or best solution. 

Are you convinced by the explanation ? 

Regards,

Kaushik  

[Pankaj Srivastava]

Hello Mr. Deka,

Thank You very much for your explanation. You are quite learned. Still, I would like to ask few questions: 

Which information in the Question implied linear growth?

Did they teach us Law of Parsimony or did they assume that candidates are already aware of such a law?

You introduced me to law of parsimony. I would like to introduce you to practical world. In practical world, increment is never a simple interest. It is always a compound interest. People get Increment on last drawn salary and not on the salary figure for which they got hired. Isn't it? You must be a working professional. So, you must be aware how it all works as far as salaries and increments are concerned. 

Thank You!

[Kaushik Deka]

Hello Mr. Srivastava,

I agree with you, unless the question hinted at linear growth - will have to wait for the questions to be released for confirmation.

Best wishes,

Kaushik  

[Kaushik Deka]

P.S.  Thank you for your kind words!

[Pankaj Srivastava]

Would love to have more interaction with you if both of us make it to Foundation Level..

Best Wishes!

[Renjith K S]

There is no ambiguity in the question of salary being a simple interest or compound interest. the equations that was given as options was linear. a general straight line equation with a slope and y intercept. for a compound interest the graph would be different due to its exponential growth. it has to be a curve.

[Kaushik Deka]

Sure! Hope we have done more than well-enough to qualify to the next level.

Best! 

[manu kumar]

Hi Renjith,

    Is that is how we are supposed to derive a question. Derive the question by looking at the allowed answers. Shouldn't the clarification be in question itself? I'm not sure if that's a valid expectation.

[Renjith K S]

i am not here to comment on how the question should be derived. but there is a smart way of doing problems right? especially for time constrained problems. I don't remember the whole question but by just finding the slope itself we can choose the answer because i think there was no two linear equations with the same slope and two different y intercepts. also the same applies for wifi question where the only thing we had to do was just to find the intercepts and compare it with the range. for this problem if there was an option none of these then the argument of compound interest was valid. 

now you asked me is that the way to derive a question? well my answer is yes because the answer they were expecting was those.

[Kaushik Deka]

After going over the question - 91 from Q1QP3, nowhere does it mention that the increments are linear. Annual increment rate for Sonia will be 1 or 0.07 depending on the growth curve one assumes. 

So, Mr. Srivastava, you are spot on with your query.  

Thank you!

[Kaushik Deka]

Sorry, the given annual increments are in lakh Rs., constant for an employee, which is NOT = interest rate. So, this implies linear growth ! Hope this clarifies the doubt. On the day, I calculated the wrong answer though. :)

[Pankaj Srivastava]

Thank you Mr. Deka! I have realized my mistake. But, I hope, that you would agree that it was a very confusing question. May be if they would have added (Rupees in lakhs) in the Table then it would have been much easier for the candidates to understand the question. In statistical charts also that keep appearing in various newspapers and magazines or news channels, they don't mention something that is part of statistical chart anywhere in the article. Such information is always highlighted with the statistical chart. Do you agree?

So, according to our lessons of Statistics, this question qualifies for manipulation of data as it caused lot of confusion to lot of candidates. 

[Pankaj Srivastava]

Hope everyone in this thread has made the cut

Little upset 'coz of obvious reasons, but;

Wrong concepts, in my brain, no one can enforce

Have I learnt a lesson? Of course!

Fighting for minuscule is not my aim

Glad that I am in for the Game

Thanking everyone who participated in the Discussion!

[Pankaj Pandey]

I scored the following...will I be selected?

Eng - 48

CT - 50

Statistics - 42

Maths - 48

Please let me know😂😂😂😂

On Mon, 30 Nov, 2020, 10:56 pm Pankaj Srivastava, <pankaj...@gmail.com> wrote:

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[Yashwardhan Banta]

Big reason to worry (virus' tone)! I'm really sorry but you won't pass this time around, try next time maybe? XDXDXD

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[Pankaj Srivastava]

What's this mostwanted? Could not understand..