Maths / Arithmetic Progression / Find Last Term When First Term, Number of Terms and Sum of N Terms is Given

QUESTION

Find the 14th term of an AP whose first trem  x+2 and sum of 14 terms is 42x-14

 OPTIONS A. 5x-2 B. 7x-4 C. 5x D. 5x-4
Right Option : D

EXPLANATION
Explain TypeExplanation Content
Text

$\dpi{120} \fn_jvn \large S_n = \frac{n}{2}(a+l)$

$\dpi{120} \fn_jvn \large \dpi{120} \fn_jvn \large 42x-14 = \frac{14}{2}(x+2 +l)$

42x-14 = 7(x+2+l)

6x-2= x+2+ l

l = 6x-2-x-2 = 5x-4

View Contents
(Concept based Learning and Testing for [6th - 10th], NTSE, Bank & Govt. Exams)
Self Learning
Testimonials
PARENT FEEDBACK c/o Manish Kumar C/o ABHYAS Academy
10th
Abhyas is good institution and a innovative institute also. It is a good platform of beginners.Due to Abhyas,he has got knoweledge about reasoning and confidence.My son has improved his vocabulary because of Abhyas.Teacher have very friendly atmosphere also.

#### Other Testimonials

Courses We Offer
(Concept based Learning and Testing for [6th - 10th], NTSE, Bank & Govt. Exams)