Part A
<h3>Answer: Histogram</h3>
Explanation:
A histogram is best because it helps show how the scores breakdown for the various bins or intervals or classes. It's effectively a visual summary of a grouped frequency table.
A dot plot would not work because we don't know the specific scores, but rather just the general region of where they fall.
A box plot doesn't work well either because we lose information on how the distribution is broken down. Sure we get the five number summary out of it, but we don't see how the bins are set up.
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Part B
We have the categories or bins of 0-4, 5-9, 10-14, 15-19, 20-24. Each bin will correspond to a bar that tells us how frequently the values show up. It tells us how frequent or how many scores we got in that sub-interval.
- The bin 0-4 has a bar that is 4 units high which means we got 4 scores that are between 0 and 4
- The bin 5-9 has a bar that is 5 units high, so we have 5 scores between 5 and 9.
- The bin 10-14 has a bar that is 2 units high since we have 2 scores in this region.
And so on. This all leads to the histogram shown below.