Thank you for the question, Shelley!
I would reason that the word problem in the example you describe is displayed to the explanatory paragraph, which happens to follow instead of precede it.
However, this is at odds with the wording of BF2016 9.2.2.
"The adjusted margin is 2 cells to the right of the runover position for the material that precedes displayed matter."
Without seeing the print in question, I dare not build an exceptional case for formatting the word problem as if it is displayed to what follows it instead of what precedes it.
I regret that I cannot be more definite.