The weight of a bag of sugar, WWW, is modeled by a normal distribution with a standard deviation of 12 g. It is known that P(W<490)=0.2P(W < 490) = 0.2P(W<490)=0.2.
Calculate the mean weight of the bags of sugar.
48 exam-style questions on Edexcel A Level Maths 3.5 Finding the mean and standard deviation. Each one has a worked solution and a mark scheme showing where the marks go.