Answer: Choice C
1, 3, 6, 8, 10, 12, 13, 13, 16, 18, 19
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Step-by-step explanation:
For each answer choice, there are n = 11 numbers mentioned.
The median will be at slot n/2 = 11/2 = 5.5 = 6, so there are 5 values below the median and 5 values above it. In total, we have 5+1+5 = 11 items overall.
The vertical bar in the box plot represents the median's location. It's at 12, so "12" must be in slot 6 in the answer.
Based on this alone, the answer is between choice A or choice C. These two answers are nearly identical except for one thing: the max for choice A is 20 while the max for choice C is 19.
The answer is choice C because the boxplot shown has the tip of the right whisker at 19, and not 20.
Side note: the data values must be sorted before you can find the median. Luckily, for each answer choice, the values are already sorted for us.