39+8=47, ET=3/11, nothing to correct 47+8=55, ET=(3+3)/11=6/11, correction: 55+1=56, ET=(6-11)/11=-5/11. 56+8=64, ET=(-5+3)/11=-2/11, nothing to correct 64+8=72, ET=(-2+3)/11=1/11, nothing to correct 72+8=80, ET=(1+3)/11=4/11, nothing to correct 80+8=88, ET=(4+3)/11=7/11, correction: 88+1=89, ET=(7-11)/11=-4/11 And so on...