In the winter, I try and climb up an icy slope starting at the bottom. Each time I
make a move I find that I go up four metres but then slide back down two metres.
How many moves do I need to get to the top which is 8 metres up the slope from
I think the answer is three because once you are at the top you can move on.
First move: up 4 to 4 metres from top but slip back 2 - so now 6 metres from the top
Second move: up 4 to 2 metres from the top but then slip back 2 - so now 4 metres from the top
Third move: up 4 metres so at the top.
There are other problems like this - frog in a well etc.