Question

Random numbers in a data set are given as 15 , 25 , 35 , 35 and 40 . All the numbers are divided by 5 , then multiplied by 2 followed by addition of 3. What will be the mean of new data set ?

• A. 30
• B. 12
• C. 6
• D. 15

Answer 1

The correct option is D 15

Numbers are given as 15 , 25 , 35 , 35 and 40.

Average of their ages is given by

$\frac{SumofObservations}{No.ofObservations}$

= $\frac{15+25+35+35+40}{5}$

= 30

If all the members are divided by 5 then multiplied by 2 followed by addition of 3 , this same mathematical operation will done to the initial mean also.

So new mean $=(\frac{30}{5}\times 2)$ + 3 = 15