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ERIC Number: EJ943281
Record Type: Journal
Publication Date: 2011-Dec
Pages: 15
Abstractor: As Provided
Reference Count: 0
ISSN: ISSN-0732-3123
Why It Is Important for In-Service Elementary Mathematics Teachers to Understand the Equality 0.999...=1
Yopp, David A.; Burroughs, Elizabeth A.; Lindaman, Brian J.
Journal of Mathematical Behavior, v30 n4 p304-318 Dec 2011
Researchers conducted semi-structured interviews with in-service fifth grade teachers. The purpose of these interviews was to examine teachers' reactions to arguments that 0.999... = 1. Previously reported results indicate that some pre-service elementary school teachers possess misunderstandings about mathematical issues related to decimals with single repeating digits. This research investigates whether some in-service teachers possess misunderstandings about mathematical issues related to 0.999.... This paper reports on one instance of a teacher whose responses indicate that the teacher's sense of number and sense of measurement are intertwined, resulting in fragile understanding of repeating decimals. These data present evidence that teachers continue to develop repeated decimal understandings and misunderstandings throughout their careers, and that the curriculum, everyday experience, and perceptions of student learning combine to form or reinforce these understandings. Because decimals with a single repeating digit (e.g. 0.333... and 0.666...) are an integral part of the elementary mathematics curriculum, we argue that it is important that in-service elementary mathematics teachers have a clear understanding of concepts related to the concept of infinity as they emerge through the study of the equality 0.999... = 1. (Contains 2 illustrations.)
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Publication Type: Journal Articles; Reports - Research
Education Level: Elementary Education
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A