Question

the average time to print a job in the computer laboratory is known to be 30 seconds. the standard deviation of the printing time is 4 seconds. compute a bound on the probability that the printing time is between 20 and 40 seconds.

Answer 1

To compute the bound on the probability that the printing time is between 20 and 40 seconds, we can standardize the values and find the areas under the standard normal distribution curve.

Step-by-step explanation:

To compute the probability that the printing time is between 20 and 40 seconds, we need to standardize the values of 20 and 40 using the z-score formula. The z-score = (x - µ) / σ where x is the value, µ is the mean, and σ is the standard deviation.

Using the z-score, we can find the area under the standard normal distribution curve. The probability of the printing time being between 20 and 40 seconds is the difference between the areas under the curve corresponding to the z-scores of 20 and 40.

Using a standard normal distribution table or a calculator, we can find the probabilities corresponding to the z-scores of 20 and 40. Finally, we subtract the probability corresponding to the z-score of 20 from the probability corresponding to the z-score of 40 to find the bound on the probability.