Question

If each observation of the data is decreased by 15; then the mean ______.

Options

• remains same

• is increased by 15

• is decreased by 15

• is multiplied by 15

Answer 1

If each observation of the data is decreased by 15; then the mean is decreased by 15.

Explanation:

When a constant value is subtracted from every individual observation in a dataset, the overall mean of the dataset decreases by that exact same constant. Therefore, decreasing each observation by 15 reduces the mean by 15.