On a recent test, students had the following scores: 85, 100, 92, 96, 87, 94, 75. For these scores, find: a) Mean b) Variance = sum of (Difference from the Mea
Mathematics
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Question
On a recent test, students had the following scores: 85, 100, 92, 96, 87, 94, 75. For these scores, find: a) Mean b) Variance = sum of (Difference from the Mean)^2 c) Standard Deviation = Square root of the variance
1 Answer

1. User Answers Edufirst
a) Mean = [85+100+92+96+87+94+75] / 7 = 89.86
b) Variance = sumatoria (value  mean)^2 / (n1)
{ (85  89.86)^2 + (10089.86)^2 + (9289.86)^2 + (9689.86)^2 + (8789.86)^2 + (9489.86)^2 + (7589.86)^2 } / (71) = 423.02/6 =70.5
c) Standard deviation = √variancia
= 8.40