3

[12 marks]

The inside diameter of a piston ring is normally distributed with a mean of 4.5 cm and a

standard deviation of 0.005 cm.

(a)

(b)

What is the probability of a diameter exceeding 4.51 cm?

What is the probability that a diameter is between 4.49 cm and 4.51 om?

[15 marks]

[15 marks]