Question

An industrial sewing machine uses ball bearings that are targeted to have a diameter of 0.78 inch. The lower and upper specification limits under which the ball bearings can operate are 0.76 inch and 0.80

​inch, respectively. Past experience has indicated that the actual diameter of the ball bearings is approximately normally​ distributed, with a mean of

0.782 inch and a standard deviation of 0.008 inch. Complete parts​ (a) through​ (e) below.

a. What is the probability that a ball bearing is between the target and the actual​ mean?

​(Round to four decimal places as​ needed.)

b. What is the probability that a ball bearing is between the lower specification limit and the​ target?

​(Round to four decimal places as​ needed.)

c. What is the probability that a ball bearing is above the upper specification​ limit?

​(Round to four decimal places as​ needed.)

d. What is the probability that a ball bearing is below the lower specification​ limit?

nothing

​(Round to four decimal places as​ needed.)

e. Of all the ball​ bearings, 94​% of the diameters are greater than what​ value?

Answer 1