To determine which family has more consistent scores, we can look at the range of each family's IQ scores. The range is calculated as the difference between the highest and lowest scores.
Family A Scores:
109, 113, 117, 120, 128, 111
- Lowest score = 109
- Highest score = 128
- Range = 128 - 109 = 19
Family B Scores:
120, 118, 115, 116, 119, 118
- Lowest score = 115
- Highest score = 120
- Range = 120 - 115 = 5
Comparison of Ranges:
- Family A has a range of 19.
- Family B has a range of 5.
Since a lower range indicates more consistency in scores, we can conclude that Family B has more consistent scores.
Therefore, the correct response is:
Family B is more consistent, because the range of their scores is lower than that of Family A.