Use the following scenario to answer the next 4 questions. An industrial sewing machine uses ball bearings that are targeted to have a diameter of 0.75 inch. The specification limits under which the ball bearing can operate are 0.74 inch (lower) and 0.76 inch (upper). Past experience has indicated that the actual diameter of the ball bearings is approximately normally distributed with a mean of 0.753 inch and a standard deviation of 0.004 inch. So we have that the diameter of the ball bearings is approximately normal with µ = .753 in. and ? =.004 in.
1) What is the probability that a ball bearing will be between the target and the actual mean?
2) What is the probability that a ball bearing will be between the lower specification limit and the target?
3) What is the probability that a ball bearing will be above the upper specification limit?
4) What is the probability that a ball bearing will be below the lower specification limit?