UPSC Exam > UPSC Questions > The average of 9 numbers is 30. The average o...
Start Learning for Free
The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?
- a)20
- b)30
- c)40
- d)50
Correct answer is option 'C'. Can you explain this answer?
| FREE This question is part of | Download PDF Attempt this Test |
Verified Answer
The average of 9 numbers is 30. The average of first 5 numbers is 25 a...
Given,
The average of 9 numbers is 30.
Thus, the total sum of 9 numbers = 9 x 30 = 270,
Also, the average of first 5 numbers is 25,
So, the total sum of 5 numbers = 5 x 25 = 125
And, the average of the first 3 numbers is 35,
So, the total sum of last 3 numbers = 3 x 35 = 105
Therefore, the sum of 8 numbers out of 9 numbers = 125 + 105 = 230
Hence, the sixth number = Total sum of 9 numbers - Total sum of 8 numbers
= 270 - 230
= 40
Most Upvoted Answer
The average of 9 numbers is 30. The average of first 5 numbers is 25 a...
Given:
- Average of 9 numbers = 30
- Average of first 5 numbers = 25
- Average of last 3 numbers = 35
To Find: The 6th number
Solution:
Let's assume the sum of all 9 numbers = x
Then, we know that the average of 9 numbers is 30, so we can write:
x/9 = 30
Solving for x, we get:
x = 270
Now, we know the sum of all 9 numbers, we can find the sum of the first 5 numbers and the sum of the last 3 numbers.
Sum of first 5 numbers = 5 * 25 = 125
Sum of last 3 numbers = 3 * 35 = 105
Sum of the 6th and 7th number can be found by subtracting the sum of the first 5 numbers and the last 3 numbers from the sum of all 9 numbers:
Sum of 6th and 7th number = 270 - 125 - 105 = 40
Since the average of the last 3 numbers is 35, we know that the sum of the last 3 numbers is 3 * 35 = 105. Therefore, the sum of the 6th and 7th number is 40. We can assume that the 6th number is n, then the 7th number will be 40 - n.
So we can write:
(n + 40 - n)/2 = 35
Solving for n, we get:
n = 40
Therefore, the 6th number is 40, which is option C.
- Average of 9 numbers = 30
- Average of first 5 numbers = 25
- Average of last 3 numbers = 35
To Find: The 6th number
Solution:
Let's assume the sum of all 9 numbers = x
Then, we know that the average of 9 numbers is 30, so we can write:
x/9 = 30
Solving for x, we get:
x = 270
Now, we know the sum of all 9 numbers, we can find the sum of the first 5 numbers and the sum of the last 3 numbers.
Sum of first 5 numbers = 5 * 25 = 125
Sum of last 3 numbers = 3 * 35 = 105
Sum of the 6th and 7th number can be found by subtracting the sum of the first 5 numbers and the last 3 numbers from the sum of all 9 numbers:
Sum of 6th and 7th number = 270 - 125 - 105 = 40
Since the average of the last 3 numbers is 35, we know that the sum of the last 3 numbers is 3 * 35 = 105. Therefore, the sum of the 6th and 7th number is 40. We can assume that the 6th number is n, then the 7th number will be 40 - n.
So we can write:
(n + 40 - n)/2 = 35
Solving for n, we get:
n = 40
Therefore, the 6th number is 40, which is option C.
Attention UPSC Students!
To make sure you are not studying endlessly, EduRev has designed UPSC study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in UPSC.
|
Explore Courses for UPSC exam
|
|
Similar UPSC Doubts
Top Courses for UPSCView all
The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer?
Question Description
The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer? for UPSC 2024 is part of UPSC preparation. The Question and answers have been prepared according to the UPSC exam syllabus. Information about The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for UPSC 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer?.
The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer? for UPSC 2024 is part of UPSC preparation. The Question and answers have been prepared according to the UPSC exam syllabus. Information about The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for UPSC 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer?.
Solutions for The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer? in English & in Hindi are available as part of our courses for UPSC.
Download more important topics, notes, lectures and mock test series for UPSC Exam by signing up for free.
Here you can find the meaning of The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer?, a detailed solution for The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer? has been provided alongside types of The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice The average of 9 numbers is 30. The average of first 5 numbers is 25 and that of the last 3 numbers is 35. What is the 6th number?a)20b)30c)40d)50Correct answer is option 'C'. Can you explain this answer? tests, examples and also practice UPSC tests.
|
|
Explore Courses for UPSC 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
|
Follow Us
|
Signup to see your scores
go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup