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A sample of 14 students was selected to estimate the average score in a given quiz. The average score in the sample is 2.14 with standard deviation of 1.29. Find a 99% confidence interval for the average score of the student in the class

User Tfboy
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1 Answer

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The average score of the student in the class at a 99% confidence lies between 1.252 and 3.028

Step-by-step explanation:

Given values are

n = 14 = 2.14 σ = 1.29 z value for 99% confidence = 2.576

The mean is known one

= (z σ/√14)

= (2.576 ×1.29÷√14)


(2.576 ×1.29÷√14)

= 2.576 × 0.345

= 0.888

= mean- 0.888 = 2.14 - 0.888 = 1.252

= mean+0.888 = 2.14 + 0.888 = 3.028

The average score of the students in the class at a 99% confidence lies between 1.252 and 3.028

User Matto
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