That sounds like a test question.
More rationale answer
I sit about 3.5 m away. My speakers' sensitivity is about 88db. I need about 95db at listening position. Budgeting for headroom of 5db, my amp needs to pump out about 200 watts at 8 ohm. My current Denon provides only 80 watts
Not so rationale one:
Considering I just spend $3000 on building my own speakers (one could argue parts in it are from speakers in $8K+ range), using a $500 receiver sounds ridiculous