Question

Q1-. A normal distribution has a mean of 15 and a standard deviation of 2. Find the value that corresponds to the 75th percentile. Round your answer to two decimal places.

Q2-.Tyrell's SAT math score was in the 64th percentile. If all SAT math scores are normally distributed with a mean of 500 and a standard deviation of 100, what is Tyrell's math score? Round your answer to the nearest whole number.

Q3-.Find the z-score that cuts off an area of 0.9842 to the left of the z-score. The values in the table below represent areas to the left of the specified z-score. Round your answer to two decimal places.

Q4-. Find the area to the right of the z-score 0.41 under the standard normal curve.

Q5-.Find the area to the right of the z-score 1.40 and to the left of the z-score 1.58 under the standard normal curve.

Q6-. Determine the area under the standard normal curve that lies to the right of the z-score 0.05 and to the left of the z-score 0.25.

Q7-.A normal distribution is observed from the times to complete an obstacle course. The mean is 69 seconds and the standard deviation is 6 seconds. Using the Empirical Rule, what is the probability that a randomly selected finishing time is greater than 87 seconds? Provide the final answer as a percent rounded to two decimal places.

Q8-. A normal distribution is observed from the body weights of the forty students in a class. If the mean is 125 pounds and the standard deviation is 9 pounds, what is the probability that a randomly selected student has a body weight between 116and 134 pounds? Use the empirical rule. Provide the final answer as a percent.

Q9-.Mr. Benson's statistics test scores are normally distributed with a mean score of 85 (μ) and a standard deviation of 4 (σ). Using the Empirical Rule, about 68% of the scores lie between which two values?

Answer 1

Q1-. A normal distribution has a mean of 15 and a standard deviation of 2. Find the value that corresponds to the 75th percentile.

Mean = = 15

Standard deviation = = 2

We have given P(X < x) = 0.75

z value 0.75 is 0.67

We have to find value of x

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For the remaining questions please repost!