Question 89

If $$(2n + 1) + (2n + 3) + (2n + 5) + ... + (2n + 47) = 5280$$, then whatis the value of $$1 + 2 + 3 + .. + n?$$

Correct Answer: 4851

Solution

Let us first find the number of terms

47=1+(n-1)2

n=24

24*2n+1+3+5+....47=5280

48n+576=5280

48n=4704

n=98

Sum of first 98 terms = 98*99/2

=4851

Share on Whatsapp Share on Whatsapp

Boost your CAT prep: Take All-India 3 free CAT mock tests with Video solutions

Video Solution

video

Click on the Email ☝️ to Watch the Video Solution

Create a FREE account and get:

All Quant CAT complete Formulas and shortcuts PDF
38+ CAT previous year papers with video solutions PDF
5000+ Topic-wise Previous year CAT Solved Questions for Free

CAT Quant Questions | CAT Quantitative Ability

CAT Linear Equations Questions CAT Mensuration Questions CAT Time And Work Questions CAT Logarithms Questions CAT Percentages Questions

CAT DILR Questions | LRDI Questions For CAT

CAT Venn Diagrams Questions CAT Puzzles Questions CAT Games and Tournamnents Questions CAT Data Interpretation Questions CAT Truth Lie Concept Questions

CAT Verbal Ability Questions | VARC Questions For CAT

CAT Vocabulary Questions CAT Para Jumbles Questions CAT Verbal Ability Questions CAT Critical Reasoning Questions CAT Reading Comprehension Questions

Also Read

CAT Mock Tests

CAT 2025 Course

Free CAT Preparation

CAT Questions

CAT Formulas PDF

CAT Study Material

CAT Score vs Percentile

CAT Score Calculator

CAT Percentile Predictor

CAT Sectional Tests

CAT Exam

CAT Prep Videos

CAT Registration

CAT Syllabus 2025

CAT Eligibility Criteria

CAT Admit Card

Follow us on

Boost your Prep!

Download App