Problem: The amount of detergent in bottles labelled as containing 1 litre is normally distributed with standard deviation 0.05 litres. If the probability that a "1 litre" bottle of this detergent contains less than 1 litre of detergent is 0.003, what is the mean (i.e. average) amount of detergent in the "1 litre" bottles? Explain your answers and provides examples.