The times to complete an obstacle course is normally distributed with mean 73 seconds and standard deviation 9 seconds: What is the probability using the Empirical Rule that a randomly selected finishing time is less than 100 seconds? - Provide the final answer as a percent rounded to two decimal places. Provide your answer below:

Step 1 ：The Empirical Rule, also known as the 68-95-99.7 rule, states that for a normal distribution, nearly all of the data will fall within three standard deviations of the mean. The rule is broken down as follows: 68% of data falls within the first standard deviation from the mean, 95% fall within two standard deviations, and 99.7% fall within three standard deviations.

Step 2 ：In this case, the mean is 73 seconds and the standard deviation is 9 seconds. We need to find the probability that a randomly selected finishing time is less than 100 seconds.

Step 3 ：First, we need to calculate how many standard deviations 100 seconds is from the mean. This is done by subtracting the mean from 100 and dividing by the standard deviation.

Step 4 ：Then, we can use the Empirical Rule to estimate the probability. If the number of standard deviations is less than or equal to 1, we use 68%. If it's less than or equal to 2 but greater than 1, we use 95%. If it's less than or equal to 3 but greater than 2, we use 99.7%. If it's greater than 3, we can assume the probability is very close to 100%.

Step 5 ：Let's calculate the number of standard deviations first. The z-score is 3.0, which means that 100 seconds is exactly three standard deviations away from the mean.

Step 6 ：According to the Empirical Rule, this means that approximately 99.7% of the data falls within this range. Therefore, the probability that a randomly selected finishing time is less than 100 seconds is approximately 99.7%.

Step 7 ：Final Answer: \(\boxed{99.7\%}\)