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A sample of n=6 BMI scores of a group of individuals has a mean of M = 24.5.
One new BMI score is added to the sample and the new mean is found to be M = 25.0.
What can you conclude about the value of the new BMI score?
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Let a, b, c, d, e, and f represent the scores of the 6 participants.
You are given that
= 24.5.
It means that a + b + c + d + e + f = 6*24.5 = 147. (1)
Next, they ask you to find the unknown score x from this equation
= 25.0
From the last equation
a + b + c + d + e + f + x = 7*25.0 = 175. (2)
Replace here the sum (a + b + c + d + e + f) by 147, based on (1). You will get
147 + x = 175.
Hence,
x = 175 - 147 = 28.
ANSWER. The new BMI score is 28.
Solved.
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It is a typical problem on average scores.
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