Still avoiding Christmas for another week at least, I couldn’t resist the Black Friday section of Lidl for a couple of reasons. It’s given me two very obvious questions to ask – one about percentages and the other about cost per item. The questions I can think of straight away are: How much does each screen cost per diagonal inch? and What percentage has been taken from each of the screens on sale? Further questions might be: Which screen was the best value before the sale and which one offers the best value with the new price?