Quant Exam  >  Quant Questions  >  The sum of the first 16 terms of an AP whose ... Start Learning for Free
The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively is
  • a)
    600
  • b)
    765
  • c)
    640
  • d)
    680
  • e)
    690
Correct answer is option 'D'. Can you explain this answer?
Verified Answer
The sum of the first 16 terms of an AP whose first term and third term...
1st Method:
1st term = 5;
3rd term = 15;
Then, d = 5;
16th term = a+15d = 5+15*5 = 80;
Sum = {n*(a+L)/2} = {No. of terms*(first term + last term)/2}.
Thus, sum = {16*(5+80)/2} = 680.
2nd Method (Thought Process): 
Sum = Number of terms * Average of that AP.
Sum = 16* {(5+80)/2} = 16*45 = 680.
View all questions of this test
Most Upvoted Answer
The sum of the first 16 terms of an AP whose first term and third term...
Problem: Find the sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively.

Solution:

We are given the first term (a) and the third term (c) of an AP. We need to find the sum of the first 16 terms of this AP.

Let the common difference be d. Then we have:

c = a + 2d (since the third term is obtained by adding 2d to the first term)

Substituting the given values, we get:

15 = 5 + 2d

10 = 2d

d = 5

Now we can find the sum of the first 16 terms using the formula:

Sn = n/2[2a + (n-1)d]

where Sn is the sum of the first n terms of the AP.

Substituting the values, we get:

S16 = 16/2[2(5) + (16-1)(5)]

S16 = 8[10 + 75]

S16 = 680

Therefore, the sum of the first 16 terms of the given AP is 680.

Answer: (d) 680
Explore Courses for Quant exam
The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively isa)600b)765c)640d)680e)690Correct answer is option 'D'. Can you explain this answer?
Question Description
The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively isa)600b)765c)640d)680e)690Correct answer is option 'D'. Can you explain this answer? for Quant 2025 is part of Quant preparation. The Question and answers have been prepared according to the Quant exam syllabus. Information about The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively isa)600b)765c)640d)680e)690Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for Quant 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively isa)600b)765c)640d)680e)690Correct answer is option 'D'. Can you explain this answer?.
Solutions for The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively isa)600b)765c)640d)680e)690Correct answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for Quant. Download more important topics, notes, lectures and mock test series for Quant Exam by signing up for free.
Here you can find the meaning of The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively isa)600b)765c)640d)680e)690Correct answer is option 'D'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively isa)600b)765c)640d)680e)690Correct answer is option 'D'. Can you explain this answer?, a detailed solution for The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively isa)600b)765c)640d)680e)690Correct answer is option 'D'. Can you explain this answer? has been provided alongside types of The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively isa)600b)765c)640d)680e)690Correct answer is option 'D'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively isa)600b)765c)640d)680e)690Correct answer is option 'D'. Can you explain this answer? tests, examples and also practice Quant tests.
Explore Courses for Quant exam
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev