Question

the table shows the battery lives, in hours, of ten brand a batteries and ten brand b batteries. battery life (hours) brand a 22.5 17.0 21.0 23.0 22.0 18.5 22.5 20.0 19.0 23.0 brand b 20.0 19.5 20.5 16.5 14.0 17.0 11.0 19.5 21.0 12.0 which would be the best measure of variability to use to compare the data? only brand a data is symmetric, so standard deviation is the best measure to compare variability only brand b data is symmetric, so the median is the best measure to compare variability both distributions are symmetric, so the mean is the best measure to compare variability both distributions are skewed left, so the interquartile range is the best measure to compare variability

Explanation:

Step1: Analyze data symmetry

For symmetric data, standard - deviation is a good measure of variability. For skewed data, inter - quartile range is better.

Step2: Check Brand A data

Brand A data has a relatively symmetric distribution.

Step3: Check Brand B data

Brand B data is skewed (e.g., has lower values pulling it left). So, for Brand A, standard deviation is appropriate for comparing variability.

Answer:

Only Brand A data is symmetric, so standard deviation is the best measure to compare variability.