The pth term of an AP is (3p – 1)/6. The sum of the first n terms of the AP is
  • a)
    n(3n + 1)
  • b)
    n/12 (3n + 1)
  • c)
    n/12 (3n – 1)
  • d)
    none of these
Correct answer is option 'B'. Can you explain this answer?

CA Foundation Question

2 Answers
Prerna Shankar answered Jul 02, 2018
The first term is (3*1-1)/6 = 2/6 
The nth term is (3n-1)/6 
The average of the first term and the last term is 1/2 ( 2/6 + (3n-1)/6 ) 
=(2+3n-1)/12 
= (3n+1)/12 
So the sum of the first n terms is n * (3n+1)/12 = (n/12)(3n+1). 

This discussion on The pth term of an AP is (3p 1)/6. The sum of the first n terms of the AP isa)n(3n + 1)b)n/12 (3n + 1)c)n/12 (3n 1)d)none of theseCorrect answer is option 'B'. Can you explain this answer? is done on EduRev Study Group by CA Foundation Students. The Questions and Answers of The pth term of an AP is (3p 1)/6. The sum of the first n terms of the AP isa)n(3n + 1)b)n/12 (3n + 1)c)n/12 (3n 1)d)none of theseCorrect answer is option 'B'. Can you explain this answer? are solved by group of students and teacher of CA Foundation, which is also the largest student community of CA Foundation. If the answer is not available please wait for a while and a community member will probably answer this soon. You can study other questions, MCQs, videos and tests for CA Foundation on EduRev and even discuss your questions like The pth term of an AP is (3p 1)/6. The sum of the first n terms of the AP isa)n(3n + 1)b)n/12 (3n + 1)c)n/12 (3n 1)d)none of theseCorrect answer is option 'B'. Can you explain this answer? over here on EduRev! Apart from being the largest CA Foundation community, EduRev has the largest solved Question bank for CA Foundation.