Can someone help me what is wrong with my code? I can't fint out what is wrong with it?
I get an error:
Oops, try again. grades_std_deviation(911.49) returned 18.2776094147 instead of the correct value 30.1908926665
grades = [100, 100, 90, 40, 80, 100, 85, 70, 90, 65, 90, 85, 50.5] def print_grades(grades): for grade in grades: print grade def grades_sum(grades): total = 0 for grade in grades: total += grade return total def grades_average(grades): sum_of_grades = grades_sum(grades) average = sum_of_grades / float(len(grades)) return average def grades_variance(scores): average = grades_average(scores) variance = 0 num_scores = len(scores) for score in scores: variance = variance + (average - score) ** 2 variance = variance / float(num_scores) return variance def grades_std_deviation(variance): variance = grades_variance(grades) variance = variance ** float(0.5) return variance print print_grades(grades) print grades_sum(grades) print grades_average(grades) print grades_variance(grades) print grades_std_deviation(grades)