Question: The weekly incomes of senior shift foremen at the Rolls Royce aero-engine factory in Derby are normally distributed with a mean of £1,000 and a standard deviation of £100.

(a) What is the z value for the income of a foreman who earns £1100 per week?

(b) What is the z value for the income for a foreman who earns £900 per week?

(c) What is the probability of selecting a foreman whose weekly income is:

(d) between £1,000 and £1100?

(e) who earns less than £1100?

(f) whose income is between £790 and £1,000?

(g) who earns less than £790?