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ASAP A miniature American Eskimo dog has a mean weight of 15 pounds with a standard deviation of 2 pounds. Assuming the weights of miniature Eskimo dogs are normally distributed, what range of weights would 68% of the dogs have?

Approximately 13–17 pounds
Approximately 14–16 pounds
Approximately 11–19 pounds
Approximately 9–21 pounds

2 Answers

1 vote

Answer:

Approximately 13-17 pounds.

Explanation:

68% of the normal distribution curve is an area of about 1 standard deviation each side of the mean so the answer is 15 - 2 to 15 + 2.

User Gutsygibbon
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1 vote

Answer: First Option

Approximately 13–17 pounds

Explanation:

We know that the mean weight of dogs is:


\mu = 15\ pounds

The standard deviation is:


\sigma = 2\ pounds

We are looking for a Z score for which it is met that:


P (-Z_0 <Z <Z_0) = 0.68

According to the empirical rule, for a standard normal distribution it is satisfied that 68% of the data is in a range of one standard deviation above the mean and one standard deviation below the mean. This means that:


P (-1 <Z <1) = 0.68

Then
Z_0 = 1

Therefore


\mu- \sigma<X< \mu + \sigma\\\\(15-2)<X<(15+2)\\\\13<X<17

User JasonTrue
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