The first term of an A.P is 14 and the sums of the first five terms and the first ten terms are equal is magnitude but opposite in sign. The 3rd term of the AP is
  • a)
  • b)
    6
  • c)
    4/11
  • d)
    none of these
Correct answer is option 'A'. Can you explain this answer?

CA Foundation Question

Sagarika Shinde
Jul 02, 2018
a₁ = 14 
a₅ = a₁ + 4d = 14 + 4d 
∑₅ = 5(a₁ + a₅)/2 
 = 5(28+4d)/2 
 = 70 + 10d 

a₁₀ = a₁ + 9d 
∑₁₀ = 10(a₁ + a₁₀)/2 
 = 10(28+9d)/2 
 = 140 + 45d 

∑₁₀ = -∑₅ 
140 + 45d = -70 - 10d 
55d = -210 
d = -210/55 = -42/11 

a₃ = a₁ + 2d = 70/11

Padam .
Nov 14, 2018
First term =14common diff=d==> 5/2(2*14+(4)d)=-10/2(2*4+9d)solve it d=-42/11t3=a+ 2d=70/11

This discussion on The first term of an A.P is 14 and the sums of the first five terms and the first ten terms are equal is magnitude but opposite in sign. The 3rd term of the AP isa)b)6c)4/11d)none of theseCorrect answer is option 'A'. Can you explain this answer? is done on EduRev Study Group by CA Foundation Students. The Questions and Answers of The first term of an A.P is 14 and the sums of the first five terms and the first ten terms are equal is magnitude but opposite in sign. The 3rd term of the AP isa)b)6c)4/11d)none of theseCorrect answer is option 'A'. 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 first term of an A.P is 14 and the sums of the first five terms and the first ten terms are equal is magnitude but opposite in sign. The 3rd term of the AP isa)b)6c)4/11d)none of theseCorrect answer is option 'A'. 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.
This discussion on The first term of an A.P is 14 and the sums of the first five terms and the first ten terms are equal is magnitude but opposite in sign. The 3rd term of the AP isa)b)6c)4/11d)none of theseCorrect answer is option 'A'. Can you explain this answer? is done on EduRev Study Group by CA Foundation Students. The Questions and Answers of The first term of an A.P is 14 and the sums of the first five terms and the first ten terms are equal is magnitude but opposite in sign. The 3rd term of the AP isa)b)6c)4/11d)none of theseCorrect answer is option 'A'. 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 first term of an A.P is 14 and the sums of the first five terms and the first ten terms are equal is magnitude but opposite in sign. The 3rd term of the AP isa)b)6c)4/11d)none of theseCorrect answer is option 'A'. 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.