y=84-72=12 z=84-52=32 x=84-12-32=40
72 + 72 = 144
49 + 72 + 68 = 189
72+30=102
180+72=252
You would formulate this problem X/100 * 150 = 72 and solve for X.
21 + 42 + 52 + 58 + 72 + 75 + 89 = 409
72 !
72
132
It is the property of n as the additive identity.
U = 4 x 18 U = 72