Jill Runs a Factory in Canberra That Makes Lie Detectors

Multiple Choice

Jill runs a factory in Canberra that makes lie detectors. This month, Jill's 34 workers produced 680 machines. Jill's average product of labour equalled ________ lie detectors per worker.

A) 34
B) 23
C) 680
D) 20
E) None of the above answers is correct.