Once upon a time a rather inquisitive researcher wanted to see just how fast a snail (who was a willing volunteer) could actually slither along, and whether or not they could be confused while they slept! So he put a snail into a special race track. This race track was actually just a piece of extremely stretchy elastic, which was soaked in special snail food so the snail could always keep travelling in the same direction without having to stop for food breaks.

At the start of the experiment the piece of elastic was 1 metre long, and the snail started travelling from one end to the other. After travelling 91 centimetres, the snail realised he only had 9 centimetres left to travel, so he decided to take a nap. As soon as he heard the gentle wheezing of the snail snoring, the researcher stretched the elastic until it was 10 metres long. Of course, the snail had quite a shock when he woke up (he had, after all, only travelled 91cm during the previous session), but resolutely set off on his journey again. After another 91 centimetres, he had another nap, and the researcher again stretched the elastic, so it was now 100 metres long.

This continued over and over again. Every time the snail woke up, he travelled 91 cm, always in the same direction along the race track, and then took a nap. Every time the snail took a nap, the researcher stretched the elastic by a factor of ten.

How long did it take the snail to reach the end of the elastic? Or will he never get there?