Consider a set S given as {11,22,33,44,55,66,77,88,99} . If each element of the data set is multiplied by -5 then by what factors will the Mean,Variance and Standard Deviation respectively change ?  Choose the most appropriate option.
A) -5,-5,-5 B) -5,5,5 C) 1,1,1 D) -5,25,5 E) 5,5,25
Mean: If all values are multiplied by -5 then their sum will also be multiplied by -5 so Mean will also get -5   Variance:   Variance is equal to (Sum of (Square of (the difference between mean and individual values))/Total number of values   When we multiply all the values by -5 then the difference between the mean and the individual values also gets multiplied by -5 and the square of that difference becomes 25. So, the variance gets multiplied by a factor of 25   SD:   Standard Deviation is the square root of variance so sqrt(25)=5. So SD gets multiplied by a factor of 5.   So, answer will be -5,25,5.
<result>D</result>
Consider a set S given as {11,22,33,44,55,66,77,88,99} . If each element of the data set is multiplied by -5 then by what factors will the Mean,Variance and Standard Deviation respectively change ?