Montarello and Martens (2005) found that fifth-grade students completed more mathematics problems cor- rectly when simple problems were mixed in with their regular math assignments. To further explore this phenomenon, suppose that a researcher selects a stan- dardized mathematics achievement test that produces a normal distribution of scores with a mean of A = 100 and a strudard deviation of o = 18. The researcher modifie: the test by inserting a set of very easy problems among the standardized questions, and gives the modified test to a sample of n = 36 students If the average test score for the sample is M = 104, is this result sufficient to conclude that inserting the casy questions improves student performance? Use a one-tailed test with a = .01. %3D

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