The 13- to 15-year olds spent an average of 10.8 hours studying last week. not 14. Thus, Choice A is incorrect.
Let's test Choice B. <span>The median value for the hours spent studying last week for the 13- to 15-year olds is greater than the median value for the hours spent studying last week for the 16- to 18-year olds.
The median is found by finding the middle number/set in the data given. Observe.
Therefore, Choice B is true since the </span><span>median value for the hours spent studying last week for the 13- to 15-year olds is greater than the median value for the hours spent studying last week for the 16- to 18-year olds.
As for Choices C and D, they are incorrect. C is incorrect because the range of the 13- to 15-year olds is 14 - 6 = 8 and the range of the </span>16- to 18-year olds is 18 - 3 = 15. So this means, <span>The range for the hours spent studying last week for the 13- to 15-year olds is NOT the same as the range for the hours spent studying last week for the 16- to 18-year olds. Thus, C is incorrect.
D is incorrect because the mode</span> for the 16- to 18-year olds is 9 and the mode for the 13- to 15-year olds 12. Thus, t<span>he mode for the hours spent studying last week for the 13- to 15-year olds is NOT less than the mode for the hours spent studying last week for the 16- to 18-year olds. Therefore, D is incorrect. </span>
In conclusion, Choice B is the correct answer. Happy Studying!