If you want to travel the world by only land and water, how long do you think it will take?

Answer 1

I'll stick to the standard and say 80 days. Land travel will be pretty quick with trains, it's the ocean travel thats going to take a while.

Answer 2

Depend on how much you want to see, how often you want to stop and how well you plan.
It will also depend on where you get visa and how efficient that will be.

China (Beijing) to Moscow 7 days, 3 days to London, London to USA 6 days by cruise ferry, one day to Toronto, 4 days to Vancouver, ? days to China. That makes 3 weeks plus the time needed to get from Vancouver to Beijing.

But if you use cruise lines from Australia to India, India to Africa, (cross Africa by train or bus), Africa to Europe, Europe to USA, USA to south America, go round the cape by cruise or travel overland in an area with few east-west connections, and take a cruise back to Australia it will take months, may take more than a year if you need to wait for the next cruiseline if you do want to stay in a place longer than the cruise schedule permits.