GATE 2015 EE (EE2) – Question 9
P,R,S,T,U form an arithmetic sequence. Which also do? I: 2P,2R,2S,2T,2U. II: P−3,R−3,S−3,T−3,U−3. III: P²,R²,S²,T²,U².
Practise this question in The GATE Grind →
Show answer and explanation
Correct answer: (B) I and II
Explanation
Let the original common difference be d. Multiplying every term by two changes the difference to 2d, so I remains arithmetic. Subtracting the same constant leaves each difference d, so II also remains arithmetic.
For squared terms, successive differences are 2ad+d² and then 2ad+3d², generally unequal. Thus III is not guaranteed arithmetic. The correct choice is **I and II, B**.
More Quantitative Aptitude: Data Interpretation, Arithmetic and Number Computation questions
- GATE 2015 EE (EE2) Q10
- GATE 2020 AE Q10
- GATE 2020 BT Q8
- GATE 2020 BT Q10
- GATE 2020 CY Q5
- GATE 2020 CY Q8
All Quantitative Aptitude: Data Interpretation, Arithmetic and Number Computation questions →