Question : What is the sum of the first 13 terms of an arithmetic progression if the first term is –10 and the last term is 26?
Option 1: 104
Option 2: 140
Option 3: 84
Option 4: 98
Latest: SSC CGL 2024 final Result Out | SSC CGL preparation tips to crack the exam
Don't Miss: SSC CGL Tier 1 Scorecard 2024 Released | SSC CGL complete guide
Suggested: Month-wise Current Affairs | Upcoming Government Exams
Correct Answer: 104
Solution : Given: The sum of the first 13 terms and the first term is –10 and the last term is 26. By using the formula, Sn = $\frac{n}{2}[a+l]$ Where $a$ is the first term, $l$ is the last term of the A.P., and $n$ is the number of terms. By putting the values of 1st and last term, we get, ⇒ S13 = $\frac{13}{2}$[–10 + 26] ⇒ S13 = $\frac{13}{2}$[16] $\therefore$ S13 = 13 × 8 = 104 Hence, the correct answer is 104.
Candidates can download this ebook to know all about SSC CGL.
Admit Card | Eligibility | Application | Selection Process | Preparation Tips | Result | Answer Key
Question : What is the sum of the first 9 terms of an arithmetic progression, if the first term is 7 and the last term is 55?
Option 1: 219
Option 2: 137
Option 3: 231
Option 4: 279
Question : The sum of 10 terms of the arithmetic series is 390. If the third term of the series is 19, find the first term:
Option 1: 3
Option 2: 5
Option 3: 7
Option 4: 8
Question : The 3rd and 8th terms of an Arithmetic progression are –14 and 1, respectively. What is the 11th term?
Option 1: 14
Option 2: 16
Option 3: 20
Option 4: 10
Question : Three numbers are in Arithmetic Progression (A.P.) whose sum is 30 and the product is 910. Then the greatest number in the A.P. is:
Option 1: 17
Option 2: 15
Option 3: 13
Question : If 7 times the 7th term of an arithmetic progression (A.P.) is equal to 11 times its 11th term, then the 18th term of the A.P. will be:
Option 1: 1
Option 2: 0
Option 3: 2
Option 4: –1
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile