# Statistics... I need help

. Assume that a set of test scores is normally distributed with a mean of 100 and a standard deviation of 20. Use the 68-95-99.7 rule to find the following quantities:
(Hint: Make a drawing and label first)
a. Percentage of scores less than 100
b. Relative frequency of scores less than 120
c. Percentage of scores less than 140
d. Percentage of scores less than 80
e. Relative frequency of scores less than 60
f. Percentage of scores greater than 120

1. 👍 0
2. 👎 0
3. 👁 452
1. a. In a normal distribution, the mean, median and mode have the same value. Does that help?

b. 120 = mean% + 34% (1/2 of 68%)

Use similar processes to solve the remainder of your questions.

1. 👍 0
2. 👎 0
2. if you have a body temperature of 99.00„aF, what is your percentile score?

1. 👍 0
2. 👎 0

## Similar Questions

1. ### Math

Find the mean of the data set. If necessary, round to the nearest tenth. 15.8, 14.9, 17.6, 13.4. A) 15.7 ***** B) 16.2 C) 16.7 D) 19.6 Erin wrote the following set of numbers. 37, 22, 37, 19, 34, 22, 37, 22, 32, 26, 30, 22 What is

2. ### Statistics

IQ test scores are normally distributed with a mean of 100 and a standard deviation of 15. Find the x- score that corresponds to a z-score of 2.33.

3. ### Statistics

Scores on the 1995 SAT verbal aptitude test among Kentucky high school seniors were normally distributed with an average of 420 and the SD of 80. Scores on the 1995 SAT quantitative aptitude test among Kentucky high school seniors

4. ### statistics

The test scores for 9 students on the Unit 1 test were 35, 25, 50, 95, 80, 60, 45, 100, and 90. What is the value of the second quartile for this data set?

1. ### statics

Using the 68-95-99.7rule. Assume that a set of test scores is normally distributed with a mean of 80 and a standard deviation of 25. Use the 68-95-99.7 rule to find the following quantities. percentage of scores greater than 105

2. ### Stats

A sociology professor assigns letter grades on a test according to the following scheme. A: Top 14% of scores B: scores below the top 14% and above the bottom 55% C: scores below the top 45% and above the bottom 17% D: scores

3. ### Statistics

The scores on a math test are normally distributed. if the mean is 72 and the standard deviation is six, what is the range of 98% of the scores?

4. ### Math-statistics

Assume that a set of test scores is normally distributed with a mean of 100 and a standard deviation of 20. Use the 68-95-99.7 rule to find the following quantiles: a.percentage of scores less than 100 b. relative frequency of

1. ### Programming

The raptor program displays the grade for each test score and the average of all four test scores. Use a loop to input four test scores. Validate the input. The test scores must be between 0 and 100.

2. ### Math

Suppose scores on an IQ test are normally distributed. If the test has a mean of 100 and a standard deviation of 10, what is the probability that a person who takes the test will score between 90 and 110?

3. ### stats.

The GMAT test is required for admission to most graduate programs in business. In a recent year, the GMAT test scores were normally distributed with a mean of 550 and standard deviation of 100. A. Find the first quartile for the

4. ### statistics

IQ scores are normally distributed with a mean u = 100 and a standard deviation o =15. Based on distribution, determine % of IQ scores between 100 and 120 =