Use app×
Join Bloom Tuition
One on One Online Tuition
JEE MAIN 2025 Foundation Course
NEET 2025 Foundation Course
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
0 votes
1.3k views
in Statistics by (34.5k points)
closed by

The mean of data is 10. If each observation is multiplied by 2 and 1 is subtracted from each result, the mean of the new observation is ……

A) 21 

B) 19 

C) 9 

D) 10

2 Answers

+1 vote
by (66.4k points)
selected by
 
Best answer

Correct option is: B) 19

Given that the mean of data is 10.

Let number of observations be n

\(\therefore\) Sum of original observations is \(\sum x_i = 10n\) ...(1)

Given that each observation (\(x_i\)) is multiplied by 2 and 1 is subtracted from each result.

\(\therefore\) New observations are of type (2\(x_i\)-1).

Sum of new observations = \(\sum\) (2\(x_i\)-1).

= 2\(\sum\)\(x_i\) -\(\sum\) 1

= 20n - n (\(\because\) \(\sum\)\(x_i\) = 10n & \(\sum\) 1 = n)

= 19 n

\(\therefore\) Mean of new observations = \(\frac {sum \, of \, new\,observations}{ number \, of\, observations}\)

\(\frac {19n}{n} = 19\) 

Hence, the mean of new observations is 19.

+1 vote
by (35.6k points)

Correct option is: B) 19

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...