Good question. Let's try this. How about People per meter squared. The average 2 bedroom apartment in the city near where I live is about 94 square meters. If there were say 100 people at a party in his home, then the number of people per square meter would be 100 / 94 = 1.06 people / square meter.
If however he called those in his home to join him for breakfast and 7 people responded then he would have 7 / 94 = 0.0745 people per m^2 When the number is this small, it might make sense to go the other way. (m^2 per person). 94/7 = 13.4 meters per person. That makes far more sense. It means that every person has 13.4 meters^2 that he could call his own.
Volume=legntht imes widht time height volume=11 and 3/5 times 9 times 12 and 1/2 volue=11 and 6/10 times 9 times 12 and 5/10 volume=11.6 times 9 times 12.5 volume=1305 m^3