They say that for every cigarette you smoked you have taken 5 minutes off of your life. First you need to know how many you have smoked. Example: A pack and a half a day for 45 years. 20 in a pack so 30 is a pack and a half per day. Times 356 days in a year times the number of years is the total you have smoked. Example: 30 x 365 = 10,950 x 45 = 492,750. Now times it by 5 to see how many minutes you lost for each one that you smoked. 492,750 x 5 =. 2,463,750. How much time is that many minutes? Divide that by 60 to get hours then divide that by 24 to get days and then divide that by 365 to get years, That's how many years you have lost if it's true what they say. So 2,463,750 / 60 = 41,062.5 / 24 = 1,710.9 / 365 = 4.6875. In the example it comes out to 4 years and about 7 months.