Final answer:
The probability of X being less than 28 minutes is approximately 100%.
Step-by-step explanation:
To find the probability, we need to calculate the Z-score and use the standard normal distribution table.
The Z-score formula is: Z = (X - mean) / standard deviation.
In this case, X is 28 minutes, the mean is 5.5 minutes, and the standard deviation is 1.24 minutes.
Plugging these values into the formula, we get Z = (28 - 5.5) / 1.24 = 17.5 / 1.24 = 14.11.
Using the standard normal distribution table, we can find the probability associated with a Z-score of 14.11, which will give us the probability of X being less than 28 minutes.
The probability is approximately 1.000, or 100%.