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CONFIDENCE INTERVALS USING INTERVAL ARITHMETIC

This paper deals with the surprising and interesting question posed by some students about constructing confidence intervals for mean differences in independent samples. The question was: is it possible to construct a confidence interval for the difference between two means by subtracting the intervals (an arithmetic interval operation) obtained for each parameter? Several activities created by the teacher in order to obtain an answer to this question are presented. Some other confidence intervals obtained via arithmetic interval are studied.