Demand for X Amount of X Demanded per Period Price per Amount of X Demanded $1.20 $1.10 $1.00 $0.90 $0.80 $0.70 $0.60 $0.50 $0.40 $0.30 $0.20 $0.10 $0.00 1 2 3 4 5 6 7 8 9 10 11 12 $0.50 6 At a price of $0.50, the buyer demands 6 quarts. The height of the curve at 6 units is the marginalpersonal worth of the 6th unit — $0.50.