The mean score of a competency test is 77, with a standard deviation of 4. Use the empirical rule to find the percentage of scores between 65 and 89 (Assume the data set has a bell-shaped distribution.) A. 68% B. 99.7% C. 95% D. 50%
Continuous Probability Distributions
Probability distributions are of two types, which are continuous probability distributions and discrete probability distributions. A continuous probability distribution contains an infinite number of values. For example, if time is infinite: you could count from 0 to a trillion seconds, billion seconds, so on indefinitely. A discrete probability distribution consists of only a countable set of possible values.
Normal Distribution
Suppose we had to design a bathroom weighing scale, how would we decide what should be the range of the weighing machine? Would we take the highest recorded human weight in history and use that as the upper limit for our weighing scale? This may not be a great idea as the sensitivity of the scale would get reduced if the range is too large. At the same time, if we keep the upper limit too low, it may not be usable for a large percentage of the population!
The mean score of a competency test is
with a standard deviation of
Use the
and
(Assume the data set has a bell-shaped distribution.)
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 3 images
