Popup Image
× logo

The Free 30-Day CAT RC Course

"It is designed to help you excel in the upcoming CAT 2023 exam"

-By Lavleen Kaur Kapoor. Over 1,73,000 Subscribers

read more

No thanks >

PGDM

CAT, XAT, GMAT

OPEN

PGDM

XAT, CAT, GMAT, CMAT

OPEN

MBA/PGPM

IBSAT, CAT, XAT, NMAT, GMAT

OPEN
Lavleen kaur kapoor

Get Personalized MBA Mentorship

Hope you enjoy reading this article.
Connect with my team on WhatsApp for unbiased MBA College Selection advice.


- Lavleen Kaur Kapoor

Quantitative Techniques section

CMAT Exam Date: 4th May 2023

India's Pink Revolution
MBA aspirants who are appearing in CMAT Test which will be conducted in April 2023 may find following Quantitative Techniques  
Question useful for practice: 
 
Progressions: Sum of terms of an Arithmetic Sequences
 
Question 
 
The sum of 20 terms of the series -12 + 22 - 32 + 42 - 52 + 62....  
 
1.210
2.519
3.190
4.420
 
Answer
 
Correct Choice is (1) and Correct Answer is 210
 
Explanatory Answer
 
-12 + 22 - 32 + 42 - 52 + 62.... up to 20 terms can be written as
(-12 + 22) + (-32 + 42) + (-52 + 62) +..... up to 20 terms.
= (-1 + 2) (1 + 2) + (-3 + 4) (3 + 4) + (-5 + 6) (5 + 6) +..... (-19 + 20) (19 + 20)
= (1 + 2) + (3 + 4) + (5 + 6) + ..... + (19 + 20)
Sum of the first 'n' natural numbers = n(n+1)/2
 
Therefore, sum of the given series = 20*21/2 = 210
 
 
 
 

Related Articles