Question

If the variance of a dataset is 64 and each value in the dataset is doubled, what is the new variance?

• A. 256
• B. 50
• C. 1024
• D. 58

Answer 1

Answer: (A)

256

Answer 2

If each value in a dataset is multiplied by a constant $k$, the new variance is $k^2$ times the original variance. Here, the values are doubled, so $k = 2$. The original variance is 64. Therefore, the new variance is $2^2 \times 64 = 4 \times 64 = 256$.