AR=P>MR \mathrm {AR = P> MR}AR=P>MR
MR>AR=P \mathrm {MR > AR = P}MR>AR=P
AR>P=MR \mathrm {AR > P = MR}AR>P=MR
P>AR=MR \mathrm {P > AR = MR}P>AR=MR