NDA Sequences and Series questions with solutions
AP, GP, HP, means and series. 36 questions from our 2016–2025 NDA pattern papers, from the Class 11 Mathematics syllabus. Each has the answer and a full solution.
Also practise: Sequences and Series for JEE Main · Sequences and Series for JEE Advanced
NDA 2025
NDA 2024
NDA 2023
- In an arithmetic progression the 4th term is 11 and the 9th term is 31.
- If a,b,c are in AP, then 2^a,2^b,2^c are in GP. 2. The sum of the first n odd natural numbers is n^2.
- In a geometric progression the third term is 12 and the sixth term is 96. The first term is
- The 10th term of the harmonic progression 1/3,1/5,1/7,… is
- The harmonic mean of two positive numbers is 4.8 and their arithmetic mean is 5. Their geometric mean is
NDA 2022
NDA 2021
NDA 2020
- The sum of all the multiples of 7 lying between 100 and 500 is
- In a harmonic progression the 4th term is 1/9 and the 7th term is 1/15.
- For non-zero real numbers a,b,c: 1. If a,b,c are in GP, then a^2,b^2,c^2 are in GP. 2. If a,b,c are in AP, then a^2,b^2,c^2 are in AP.
- The arithmetic mean of two positive numbers is 13 and their geometric mean is 12. Their harmonic mean is
NDA 2019
- The sum of all natural numbers between 10 and 100 that are multiples of 4 is
- In a GP the fourth term is 24 and the seventh term is 192. The sum of the first eight terms is
- If two geometric means are inserted between 3 and 81, their sum is
- The 10th term of the harmonic progression 1/2,1/5,1/8,… is
- For two distinct positive numbers, the arithmetic mean is less than the harmonic mean. 2. The sum to infinity of the GP 1-1/2+1/4-… is 2/3.
NDA 2018
NDA 2017
- Three geometric means are inserted between 3 and 48. Their sum is
- In a harmonic progression the 2nd term is 1/3 and the 5th term is 1/9.
- The arithmetic mean of two positive numbers is 5/4 times their geometric mean. The ratio of the larger to the smaller number is
- For two distinct positive numbers, AM>GM>HM. 2. An infinite GP with first term 2 and common ratio 1.5 has sum -4.
NDA 2016
- In a geometric progression of positive terms, the third term is 12 and the sixth term is 96. The eighth term is
- The sum of the first n terms of a sequence is Sn=3n^2+2n.
- The number of multiples of 6 lying between 100 and 500 is
- Three positive numbers in geometric progression have product 216 and sum 26. The greatest of them is
- The recurring decimal 0.272727… expressed as a fraction in lowest terms is
- For x>0, the minimum value of 4x+9/x+5 is
- If a, b, c are in AP, then 1/bc,1/ca,1/ab are in AP. 2. If a, b, c are positive and in GP, then log a, log b, log c are in AP.
- For x>0, x+1/x≥2. 2. For x<0, x+1/x≥2.
Other Mathematics topics
Three Dimensional Geometry 48Vector Algebra 60Complex Numbers and Quadratic Equations 35Binomial Theorem 16Quadratic Equations 27Permutations and Combinations 25Statistics 35Probability 27Matrices 37Determinants 13Sets, Relations and Functions 39Binary Number System 11Logarithms 11Inverse Trigonometric Functions 22Trigonometric Functions and Identities 49Trigonometric Equations 16Properties of Triangles 18Heights and Distances 12Straight Lines 43Circles 21Conic Sections 28Limits 23Continuity and Differentiability 16Application of Derivatives 34Derivatives 33Integrals 16Definite Integrals 23Application of Integrals 12Differential Equations 30