Final answer:
Granny's use of the word 'figgerin'' means solving a puzzle or problem.
Step-by-step explanation:
In this context, Granny's use of the word 'figgerin'' means solving a puzzle. She is not fishing for fish, but rather mentally challenging herself to solve a problem or puzzle.
For example, maybe Granny loves doing crossword puzzles or brain teasers in her free time. So when she says she's 'fishin' fer figgerin'', she means she's engaging in an activity that requires problem-solving and critical thinking.