# Homework problem. What is the answer supposed to look like?

I am taking a statistics course this semester, and this is part of our first homework assignment, only I don't know what the answer is even supposed to look like.

When the process is functioning correctly, the adhesive strength X is normally distributed with a mean of 200 N and a standard deviation of 10 N. Each hour, you make one measurement of the adhesive strength. You are supposed to inform your supervisor if your measurement indicates that the process has strayed from its target distribution.

a. Find P(X ≥ 203), under the assumption that the process is functioning correctly.

b. Based on your answer to part (a), if the process is functioning correctly, would a strength of 203 N be unusually large? Explain.

c. If you observed an adhesive strength of 203 N, would this be convincing evidence that the process was no longer functioning correctly? Explain.

Just to be clear, I don't necessarily need the answer, just what the answer would look like. I have no idea what Find P(X ≥ 203) means really. Thanks.

• Here's a hint. X is random variable with known properties. You are asked what is the probability that X exceeds 203. Intuitively, X tends to hover around 200, so the probability that X is slightly greater than the mean of 200 should be a bit less than one half. Commented Sep 17, 2014 at 4:33