SSC CHSL Exam > SSC CHSL Questions > The average of 20 numbers is 41. The average ...
Start Learning for Free
The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?
- a)51
- b)52
- c)53
- d)54
Correct answer is option 'A'. Can you explain this answer?
Verified Answer
The average of 20 numbers is 41. The average of the first 8 numbers is...
8 × 39 + 13 × 43 = 871
Since the 8th number came twice, it is added two times.
So the answer = 871 – 20 × 41 = 51
Hence, Option A is correct.
Since the 8th number came twice, it is added two times.
So the answer = 871 – 20 × 41 = 51
Hence, Option A is correct.
Most Upvoted Answer
The average of 20 numbers is 41. The average of the first 8 numbers is...
Given Information:
- The average of 20 numbers is 41.
- The average of the first 8 numbers is 39.
- The average of the last 13 numbers is 43.
Solution:
To find the 8th number, we need to first calculate the sum of all 20 numbers using the average given.
Finding the total sum of 20 numbers:
Total sum of 20 numbers = Average * Number of terms
Total sum of 20 numbers = 41 * 20
Total sum of 20 numbers = 820
Finding the sum of the first 8 numbers:
Total sum of the first 8 numbers = Average * Number of terms
Total sum of the first 8 numbers = 39 * 8
Total sum of the first 8 numbers = 312
Finding the sum of the last 13 numbers:
Total sum of the last 13 numbers = Average * Number of terms
Total sum of the last 13 numbers = 43 * 13
Total sum of the last 13 numbers = 559
Calculating the sum of the 9th to 20th numbers:
Sum of the 9th to 20th numbers = Total sum of 20 numbers - (Sum of the first 8 numbers + Sum of the last 13 numbers)
Sum of the 9th to 20th numbers = 820 - (312 + 559)
Sum of the 9th to 20th numbers = 820 - 871
Sum of the 9th to 20th numbers = -51
Calculating the 8th number:
Sum of the 9th to 20th numbers = 8th number + 9th number + ... + 20th number
-51 = 8th number + 9th number + ... + 20th number
Since we need to find the 8th number, we can rewrite the equation as:
-51 = 8th number + (sum of 9th to 20th numbers)
-51 = 8th number - 51
8th number = 0
Hence, the 8th number is 0, which is not in the answer choices provided. This indicates an error in the question or the options.
- The average of 20 numbers is 41.
- The average of the first 8 numbers is 39.
- The average of the last 13 numbers is 43.
Solution:
To find the 8th number, we need to first calculate the sum of all 20 numbers using the average given.
Finding the total sum of 20 numbers:
Total sum of 20 numbers = Average * Number of terms
Total sum of 20 numbers = 41 * 20
Total sum of 20 numbers = 820
Finding the sum of the first 8 numbers:
Total sum of the first 8 numbers = Average * Number of terms
Total sum of the first 8 numbers = 39 * 8
Total sum of the first 8 numbers = 312
Finding the sum of the last 13 numbers:
Total sum of the last 13 numbers = Average * Number of terms
Total sum of the last 13 numbers = 43 * 13
Total sum of the last 13 numbers = 559
Calculating the sum of the 9th to 20th numbers:
Sum of the 9th to 20th numbers = Total sum of 20 numbers - (Sum of the first 8 numbers + Sum of the last 13 numbers)
Sum of the 9th to 20th numbers = 820 - (312 + 559)
Sum of the 9th to 20th numbers = 820 - 871
Sum of the 9th to 20th numbers = -51
Calculating the 8th number:
Sum of the 9th to 20th numbers = 8th number + 9th number + ... + 20th number
-51 = 8th number + 9th number + ... + 20th number
Since we need to find the 8th number, we can rewrite the equation as:
-51 = 8th number + (sum of 9th to 20th numbers)
-51 = 8th number - 51
8th number = 0
Hence, the 8th number is 0, which is not in the answer choices provided. This indicates an error in the question or the options.
|
Explore Courses for SSC CHSL exam
|
|
Similar SSC CHSL Doubts
Top Courses for SSC CHSLView all
The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer?
Question Description
The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer? for SSC CHSL 2025 is part of SSC CHSL preparation. The Question and answers have been prepared according to the SSC CHSL exam syllabus. Information about The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for SSC CHSL 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer?.
The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer? for SSC CHSL 2025 is part of SSC CHSL preparation. The Question and answers have been prepared according to the SSC CHSL exam syllabus. Information about The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for SSC CHSL 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer?.
Solutions for The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for SSC CHSL.
Download more important topics, notes, lectures and mock test series for SSC CHSL Exam by signing up for free.
Here you can find the meaning of The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer?, a detailed solution for The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer? has been provided alongside types of The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice The average of 20 numbers is 41. The average of the first 8 numbers is 39 and that of the last 13 numbers is 43. What is the 8th number?a)51b)52c)53d)54Correct answer is option 'A'. Can you explain this answer? tests, examples and also practice SSC CHSL tests.
|
|
Explore Courses for SSC CHSL exam
|
|
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
|
© EduRev
|
Education Revolution
|
|
Signup to see your scores
go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup