When we drop through the hole to get the key, we end up in the Meadow Maze (P34) on the path that leads to the door.
Now that we have the key we can go through the door, but which way do we go next?
The TRICK...
See what number is on the door, then head towards a number that divides by the door number.
The door we just passed through has a number 8 on it, so we need to find which path takes us to a number that DIVIDES by 8.
The only number we can reach that divides by 8 is 72.
We go up the path to number 72 and drop down the hole. We land on number 72 in the Deep Dark Caves (P32).
The path from 72 only leads to a sum, so we can't go through a door.
Instead we just work out 7x10 = 70 and then take the path that leads to number 70.