A fourth grader was asked to round 2,749 to the nearest hundred. Student work 2,749 -> 2,750 -> 2,800 Which misconception does the student's work show?
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Answer: D. The student rounded in steps, letting the ones digit change the tens digit first.
Rounding 2,749 to the nearest hundred depends only on the tens digit, 4, so the correct answer is 2,700; the student first rounded to 2,750 and then to 2,800, which is chain rounding. Rounding to the nearest ten is tempting, but the student's final answer of 2,800 is a hundred, so the student did aim for the hundreds place.