7. The Variance passes me, but answer is wrong


#1

https://www.codecademy.com/courses/python-intermediate-en-7mgOa/2/1?curriculum_id=4f89dab3d788890003000096

My code passes this lesson, but the result I'm getting is 334.071005917, which isn't correct. What have I done wrong?


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
    for score in scores:
        variance += ((average - score) ** 2)
    total = variance / len(scores)
    return total
print grades_variance(grades)

#2

Recall that Variance is known as sigma squared, where sigma is Standard Deviation. Your answer looks correct.


#3

Ah, statistics isn't my strong suit. Thanks so much!


#4

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