How many dice does the GM roll when challenging the players?

I’d like to run a game of Roll for Shoes, but I’m not sure how many dice I roll when the characters face various challenges.

I’m under the impression that it’s supposed to be the same number of dice the character uses, but that seems to make impossible tasks far too easy to perform.

Is there a general rule saying how many dice the GM rolls against a character’s attempt at a given task? Should the GM’s dice equal the character’s dice, or should the GM’s dice vary depending on the task’s difficulty?