The United States has an aging infrastructure as witnessed by several recent disasters, including the I-35 bridge
failure in Minnesota. Most states inspect their bridges regularly and report their condition (on a scale from 1-17) to the public.
Here are the condition numbers from a sample of 30 bridges in New York State (
https://www.dot.ny.gov/main/bridgedata):
5.08 5.44 6.66 5.07 6.80 5.43 4.83 4.00 4.41 4.38
7.00 5.72 4.53 6.43 3.97 4.19 6.26 6.72 5.26 5.48
4.95 6.33 4.93 5.61 4.66 7.00 5.57 3.42 5.18 4.54.
Find the sample mean and sample standard deviation of these condition numbers.
5.328 and 0.959
5.657 and 0.935
6.657 and 0.875
5.328 and 0.975
