The probability that the diameter falls in the interval from 2499 psi to 2510 psi is 0.00798.
Step-by-step explanation:
Let's define the random variable, "Comprehensive strength of concrete". We have information that is normally distributed with a mean of 2500 psi and a standard deviation of 50 psi (or a variance of 2500 psi). In other words, .
We want to know the probability of the mean of X or that falls in the interval . From inference theory we know that :