Question

Naval vessels require exterior paint to help prevent erosion. The paint a particular company uses is expensive, so the company does not want to buy excess paint. However, it is also important that the vessel is painted from the same batch of paint material. If the amount of paint purchased is too small, the entire vessel will need to be re-painted with a new batch, which is costly. It is known that the amount of paint required to paint a surface of area 50 m2 is normally distributed with mean 6.5 L and standard deviation 0.3 L.

a) If 6.75 L of paint are available, what is the probability that the entire surface can be painted?

b) How much paint is needed so that the probability is 0.9 that the entire surface can be painted?

Answer 1