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Given a mean of 50 and a standard deviation of 10, determine the value of x which 10% of the measurements will exceed.

User Drewen
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Final answer:

To find the value of x that 10% of measurements exceed, the 90th percentile z-score (1.28) is used and the equation 1.28 = (x - 50) / 10 is solved, resulting in x = 62.8.

Step-by-step explanation:

To determine the value of x which 10% of the measurements will exceed given a mean of 50 and a standard deviation of 10, we need to use the concept of the z-score in a normal distribution. First, we find the z-score that corresponds to the 90th percentile because 100% - 10% = 90%. This means we want the z-score where 90% of the data falls below it. You can use a z-table or a calculator to find this, and you will find that the z-score for the 90th percentile is approximately 1.28.

Next, we apply the z-score formula:

Z = (x - mean) / standard deviation

Here, we plug in the z-score (1.28), the mean (50), and the standard deviation (10), and solve for x:

1.28 = (x - 50) / 10

x - 50 = 12.8

x = 62.8

Therefore, the value of x which 10% of the measurements exceed is approximately 62.8.

User Cwc
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