TSA 2011 · Question 50 · Logic
SaveI am a member of a book club. Every month I must choose at least one book. All books are sold at a discount of £2.00 on shop prices. I pay a fixed charge for postage regardless of which books I order.
Which one of the following graphs could show the relationship between the number of books ordered in a month and the total saving on shop prices (allowing for postage charge)?