Mariyam is designing shelves for a bookshop. The height, H cm, of books is modelled by the normal distribution with mean 25.1 cm and standard deviation 5.5 cm. (a) Complete the statement H ~ N(, )
(b) Show that P(H > 30.8) = 0.15 correct to 2 decimal places.
(c) Hence find P(30.8 < H < 40.5).
Mariyam decided that the smallest 5% of books would not be placed on the shelves.
All the other books will be placed on the shelves.
(d) Using ( < ) = 0.005, find the minimum height of books (y) that will be placed on the shelves.