Mathematics scares and depresses most of us, but politicians, journalists and everyone in power use numbers all the time to bamboozle us.Most maths is really simple - as easy as 2+2 in fact.Better still it can be understood without any jargon, any formulas - and in fact not even many numbers.Most of it is commonsense, and by using a few really simple principles one can quickly see when maths, statistics and numbers are being abused to play tricks - or create policies - which can waste millions of pounds.It is liberating to understand when numbers are telling the truth or being used to lie, whether it is health scares, the costs of government policies, the supposed risks of certain activities or the real burden of taxes.