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Typing speed is approximately normal, with a mean speed of 43 words per minute and a standard deviation of 12 words per minute. What is your typing speed if you are at the 92nd percentile?

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User Asaka
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Final answer:

The typing speed at the 92nd percentile for a normal distribution with a mean of 43 words per minute and a standard deviation of 12 words per minute is approximately 59.92 words per minute.

Step-by-step explanation:

To find the typing speed that corresponds to the 92nd percentile given a normal distribution with a mean of 43 words per minute and a standard deviation of 12 words per minute, we can use the z-score formula. First, we determine the z-score that corresponds to the 92nd percentile. In standard normal distribution tables, or using software or a calculator that provides this functionality, we see that a z-score of approximately 1.41 corresponds to the 92nd percentile. Next, we apply the z-score formula to find the specific typing speed.

The formula is:
X = μ + (z × σ)
where X is the value for the percentile, μ is the mean, z is the z-score, and σ is the standard deviation.

Plugging in the values:
X = 43 + (1.41 × 12)

= 43 + 16.92

= 59.92
Thus, the typing speed at the 92nd percentile is approximately 59.92 words per minute.

User Wilco
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