## Elementary Statistics: A Step-by-Step Approach with Formula Card 9th Edition

$86\%$
Chebyshev’s theorem The proportion of values from a data set that will fall within k standard deviations of the mean will be at least $1−1/k^2$, where k is a number greater than 1 (k is not necessarily an integer). 38. Trials to Learn a Maze The average of the number of trials it took a sample of mice to learn to traverse a maze was 12. The standard deviation was 3. Using Chebyshev’s theorem, find the minimum percentage of data values that will fall in the range of 4–20 trials. $3k=20-12$ so $k=8/3$ and $1-(3/8)^2=0.86$