Question

Mr. Harrison grades his test on a scale of 1 to 10. The dot plots below show the grades for his first test and the last test of the year. Pic below What is the difference between the means of the scores for the two tests?

Answer 1

a

Explanation:

Answer 2

Answer: 0.88

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Work Shown:

F = first test data set

F = {1,3,5,5,7,7,7,8,8,8,8,9,9,9,9,9,9,9,9,10,10,10,10,10,10}

m = mean of set F

m = (sum of values in set F)/(number of values in set F)

m = (1+3+5+5+7+7+7+8+8+8+8+9+9+9+9+9+9+9+9+10+10+10+10+10+10)/25

m = 199/25

m = 7.96

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L = last test data set

L = {3,4,4,5,5,6,6,6,7,7,7,7,7,7,8,8,8,8,8,9,9,9,9,10,10}

n = mean of set L

n = (sum of values in set L)/(number of values in set L)

n = (3+4+4+5+5+6+6+6+7+7+7+7+7+7+8+8+8+8+8+9+9+9+9+10+10)/25

n = 177/25

n = 7.08

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d = difference in means

d = m - n

d = 7.96 - 7.08

d = 0.88