Operational research : methods and examples 35اسلاید •Definitions found on the internet: –"Mathematical common sense " –" Systematic study , by observation and experiment, of the working of a system, e.g. health services, with a view to improvement " "Using scientific methods to attack a complex problem or system •Profession: unemployed: 26%, labourers 21%, students of vocational schools 19%, disabled 7% •Education: incomplete secondary edu ...