JEE Main 2020MathematicsSequences and SeriesEasyMCQ

JEE Main 2020 — Sequences and Series Question with Solution

JEE Main 2020 (08 Jan Shift 2)

Question

If the 10th, term of an A.P. is 120, and its 20th, term is 110, then the sum of its first 200, terms is.

Choose an option

Show full solutionCorrect option: D
Correct answer
D10012

Step-by-step explanation

Let, a & d is the first term and common difference of arithmetic progression respectively, then

T10=120=a+9d    ...i
T20=110=a+19d    ...ii

After solving i and ii, we get
a=1200, d=1200

Now

S200=20022200+199200=2012=10012.

Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Sequences and Series chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

About this question

This is a previous-year question from JEE Main 2020, covering the Sequences and Series chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.