Id reason like: population * % with a cellphone (assuming one charger per cellphone) / life of a charger (..?) Or is there a better way to do it?
(editiert)
Id reason like: population * % with a cellphone (assuming one charger per cellphone) / life of a charger (..?) Or is there a better way to do it?
(editiert)
I like your approach, but I would definitely also include additional cellphone chargers that are going to be sold because the old one broke or got lost (approximately maybe 10% of sold cellphones?)