[pdurrant]

Originally Posted by pdurrant

Then again, you might take the last line as referring only to the penultimate line:

Kits, cats, sacks, and wives,
How many were there going to St. Ives?

Or again, choose to interpret the question as ignoring the sacks, as mere inanimate objects.

In which case the answer is 7+7^3+7^4 = 2751