Question

The variance of a set of data is 3.If every item is doubled then, what will be the variances of the resulting data set?

Answer 1

Answer:

If each observation is multiplied by 2, then mean(μ) will get doubled.

Now, variance =σ

2

=

n

(X−μ)

2

Now here both X and μ will be doubled, so the variance will become four times.

Thus, the new variance will be 4 times the older variance which is 4×5=20.

Hence, C is correct.

Follow me

Thank my answer

Answer 2

Question :- The variance of a set of data is 3.If every item is doubled then, what will be the variances of the resulting data set ?

Solution :-

we know that,

• If we add same constant value let k in median, mean, and quartiles , they will be changed by adding constant(k) to each value.
• However, the range, interquartile range, standard deviation and variance will remain the same.

• if we Multiplying every value by a constant(k), we also have to multiply the mean, median, quartiles, range, interquartile range, and standard deviation by that constant(k), and multiply the variance (which is simply the square of the standard deviation) by the square of that constant(k).

given that,

→ Old Variance of data = 3

→ constant number is multiplied in each value = k = 2 .

therefore,

→ The variance of new data = Old Variance of data * k² = 3 * (2)² = 3 * 4 = 12 (Ans.)

Learn more :-

calculate the median and mode from the following income between (rs)100-200 100-300 100-400 100-500 100-600 no of person...

https://brainly.in/question/23585381

Some students of class X donated for the welfare of old age persons. The contributions are shown in the following distri...

https://brainly.in/question/17314012