<p>In defense of the author of the textbook or worksheet with the question
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<p>It seems to me that it is possible that the author of the text/worksheet intended that the correct answer should be “between 0 and 9, inclusive,” or “between 1 and 9, inclusive,” or “between 0 and 8, inclusive,” or “between 1 and 8, inclusive.” The “right” answer of 5 might have been supplied by the teacher, who didn’t get the intent of the text/worksheet author.</p>
<p>I prefer the first answer, “between 0 and 9, inclusive,” on mathematical grounds. However, I could see someone arguing that if you give your brother all the marbles, you wouldn’t describe that as “some.” I can also see arguing that if you give your brother a single marble, you wouldn’t describe that as “some,” either.</p>
<p>Of course, the teacher may have been the author of the worksheet. If so, this makes me imagine the scenario at her house, on a birthday: “Would you like some birthday cake?” A guest answers “Yes,” and gets served half of the cake.</p>