Suppose X is normally distributed with H = 126 and unknown o. A sample of 27 observations yields a mean, =122 and a standard deviation of 3. Find the value of the test statistic to conduct a two sided t-test.

Suppose babies born after a gestation period of 32 to 35 weeks have a mean weight of 3000 grams and a standard deviation of 600 grams while babies born after gestation period of 40 weeks have a mean weight of 3200 grams and a standard deviation of 440 grams. If a 32 week gestation period baby weighs 3225 grams and a 41 week gestation  and 41 week gestation period baby weighs 3425 grams find the corresponding z scores which baby weigh more relative to the gestation period

Assume that adults have IQ scores that are normally distributed with a mean of 107 and a standard deviation of 15. Find the third quartile Upper Q 3​, which is the IQ score separating the top​ 25% from the others.

The scores for female students had a mean of 146 with standard deviation of 35.   you can infer that 97.72% of the female students have scores above (give an x value)

For a population with  = 150, a raw score of X = 125 corresponds to z = -2.00.  What is the standard deviation?

Assume that a set of test scores is normally distributed with a mean of 110 and a standard deviation of 5. Use the Empirical Rule to find the percentage of scores greater than 110.

Assume that an intelligence test scores are distributed normallt with a mean of 100 and a standard deviation of 15. If you scored 124 on this intelligence test, what is your z-score on this distribution.

Scores on the common final  exam in Elementary Statistic course are normally distributed with mean 70 and standard deviation 10. The department has the rule that in order to receive an A in the course his score must be in top 10% of all exam scores. The minimum exam score to receive A is about

The scores on a standardized test are normally distributed with a mean of 120 and standard deviation of 20. What test score is 0.9 standard deviations above the mean?

When engaging in weight-control (fitness/fat burning) types of exercise, a person is expected to attain approximately 60% of his or her maximum heart rate. For 20-year-olds, this rate is approximately 120 bpm. A simple random sample of one hundred 20-year-olds was taken, and the sample mean was found to be 107 bpm, with a standard deviation of 45 bpm. Researchers wonder if this is evidence to conclude that the expected level is actually lower than 120 bpm. To determine this, we test the following hypotheses: Ho: H= 120 versus H₂ μ< 120 Suppose the mean and standard deviation obtained were based on a sample of size 25 rather than 100.