Your question is Expected Rolls for Dice. 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).
Explain how you would compute the expected number of rolls to see all faces of a fair dice.
Use the coupon collector approach: decompose the process into waiting times for each newly observed face. State the assumptions, derive the expectation, and provide the exact numerical result. A short simulation may be used to verify the calculation.
