Where's the answer? You asked how many immature people does it need to change a light bulb - and then you didn't tell us! So who's the immature one now, eh?
I consider changing a lightbulb a blue job and therefore wouldn't expect my mum or anyones mum to change a bulb. In the same way she wouldn't put out the bins. I wouldnt want her up a ladder at her age either
Before we know it there'll be Light Orbs that float around the room, which can sense where people are, where they would prefer the light to be, and at what level, doing away with the need for bulbs. When that day comes, it'll put the nail in the coffin of 'the light bulb' joke!