A salesman's income consists of commission and base salary

A salesman's income consists of commission and base salary. His weekly income totals over the past 5 weeks have been $406, $413, $420, $436 and $395. What must his average (arithmetic mean) income over the next two weeks be to decrease his average weekly income to $400 over the 7-week period?

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #42004