Question: The MH Company manufactures resistors with an ideal resistance value of 400 ohms. A sample of 2 000 resistors were tested and found to have a mean resistance of 391.5 ohms with a standard deviation of 22.5 ohms. Assume a normal distribution.
(a) If the ideal resistor (400 ohms) has a manufacturing tolerance of:!: 10% (:!:40 ohms), find the number of resistors from the sample that are expected to be satisfactory.
(b) Repeat part (a) for a tolerance of 1 %.
(c) Given a tolerance of ±10%, what is the probability that a particular resistor will be unusable?
(d) Find the number of sample resistors with values exceeding 425 ohms.