GATE 2020 MA – Question 5
General Aptitude · Quantitative Aptitude: Algebra, Geometry and Mensuration · 1 mark · Multiple choice
Find the difference between the sum of the first 2n natural numbers and the sum of the first n odd natural numbers.
- $n^2-n$
- $n^2+n$
- $2n^2-n$
- $2n^2+n$
Practise this question in The GATE Grind →
Show answer and explanation
Correct answer: (B) $n^2+n$
Explanation
The first sum is $(2n)(2n+1)/2=n(2n+1)$. The sum of the first n odd numbers is $n^2$. Subtracting gives $2n^2+n-n^2=n^2+n$, option B.
More Quantitative Aptitude: Algebra, Geometry and Mensuration questions
- GATE 2020 MA Q9 – A 44 matrix M=[m ij] has all diagonal entries zero and satisfies m ij=-m ji. What is the…
- GATE 2025 CS (CS1) Q7 – In the diagram, the lines QR and ST are parallel to each other. The shortest distance…
- GATE 2025 CS (CS2) Q3 – If Pex = Qe-x for all real values of x, which one of the following statements is true?
- GATE 2025 CS (CS2) Q9 – In the given figure, PQRS is a square of side 2 cm and PLMN is a rectangle. The corner L…
- GATE 2024 CS (CS1) Q2 – If two distinct non-zero real variables x and y are such that (x+y) is proportional to…
- GATE 2024 CS (CS1) Q5 – For positive non-zero real variables p and q, if (p2+q2)= p+ q+2 3, then the value of…
All Quantitative Aptitude: Algebra, Geometry and Mensuration questions →