The distribution of grades in an introductory finance class is normally distributed, with an expected grade of 68. If the standard deviation of grades is 13, in what range would you expect 68.26 percent of the grades to fall?(Round answers to 2 decimal places, e.g. 15.25. Hint: Think in terms of what the expected highest and lowest scores would be for68.26% of the students taking the exam.)

68.26 percent of the grades should fall between the ranges (lower end)______ and upper end______

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