Your question is Deciding Signal vs Noise. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You are reviewing a metric change after a product launch. The team wants to know whether the observed move is real or just noise in the data.
How would you decide whether a metric change is statistically significant or just noise?