I am struggling with this question. The following information was gathered for the Boiling Springs Corporation for the most recent year. Manufacturing overhead is allocated using machine hours.

Actual machine hours

138,000

Allocated manufacturing overhead

$1,125,000

Estimated manufacturing overhead costs

$1,050,000

Actual manufacturing overhead costs

$1,137,000

By how much is manufacturing overhead over or underallocated?

I believe I have to consider the estimated machine hours vs the actual. The verbiage they use is throwing me off and I can't figure out the equation. The answer is $12,000 underallocated but I don't know to get to that answer. I go tit wrong on a quiz