GATE CSE 2020 | Question: GA-7

Question

If $P = 3$, $R = 27$, $T = 243$, then $Q + S =$ ________

• A. $40$
• B. $80$
• C. $90$
• D. $110$

Comments

If you people who gave GATE dont know how can we know? In GO questions are added as per their ID. This question number is 7 and it should be 2 marks. But if GATE has changed this convention and mixed 1,2 marks for aptitude, it becomes hard. Unfortunately no one has confirmed us any.

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GATE OVERFLOW is absolutely spot on. From the official gate website i found that it is of 2 marks and not 1 marks.

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Its mutiples of 3 so q=9 and s=81
And q+s=90

Answer 1

We can interpret the given order as:

• $P\to 3^1= 3$
• $Q\to3^2= 9$
• $R\to3^3=27$
• $S\to3^4=81$
• $T\to3^5=243$

$Q+S\to 9+81=90$

Hence Option (C) is correct

Answer 2

Alphabetical order : P, Q, R, S, T

given that, P = 3

R=27

T = 343

 

by observing them, those are in GP with r = 3

So, Q=9, S=81

S+Q = 81+9=90

Comments

The problem with this question is that they don't give more statements like p q,r,s,t is series so how can we say Q and S is part of series the question given is incomplete.i also answered 90 but this not the way to frame question.

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Yes, ideally they have to give marks to all.

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This is a typical "inference" question. It is not a technical one and information is hidden intentionally

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Yes.
But may be the fact that you were able to reach the solution 90 was enough for them.

Answer 3

Q=3^2=9
s=3^4=81
Q+S=81+9=90

Answer 4

C is the right answer.

 Here given that P = 3 = 3^1

also R = 27 = 3^3

and T = 243 = 3^5

  now according to the sequence we clearly say that the value of Q is 3^2 = 9 and the value of S is 3^4 = 81

Now P + Q = 9 + 81 = 90                     Ans.