Here are three questions. First think fast to obtain your answers: (1) A bat and ball cost

£1.10 in total. The bat costs £1.00 more than the ball. How much does the ball cost?;

(2) It takes five machines five minutes to make five widgets, how long would it take 100 machines to make 100 widgets? (3) In a pond is a patch of lily pads. Every day, the patch doubles in size. If it takes 48 days for the patch to cover the entire pond, how long would it take for the patch to cover half the pond? The answers to these three questions are not 10p, not 100 minutes and not 24 days, respectively. Now try again, this time think slow (Frederick, 2005, p.27).