"A recent study of Greek children estimated that the average weight of a 10-year old boy was 81.57 pounds with a standard deviation of 17.41 pounds (Papadimitriou et al., 2006)." What percentage of boys weigh more than 105 pounds?
A) 1.35%
B) 8.85%
C) 58.85%
D) 91.15%

Question

Quizplus · Accepted Answer

To solve this problem, we need to use the standard normal distribution. We can convert the data to z-scores using the formula:

z = (x - μ) / σ

where x is the weight we are interested in (105 pounds), μ is the mean weight (81.57 pounds), and σ is the standard deviation (17.41 pounds).

z = (105 - 81.57) / 17.41 = 1.34

We can use a standard normal distribution table or calculator to find the probability of a z-score being greater than 1.34. This probability is approximately 0.0885, or 8.85%. Therefore, the answer is B) 8.85%.

"A Recent Study of Greek Children Estimated That the Average