Help understanding vintage dress pattern

[MissHepburn101]

Hi All,

Hoping some one can help me understand this vintage dress pattern 😊

How would you decrease as the highlighted area says? Would I miss a whole “group” (these are made of 2trtog ch1 2trtog) or would I just do a single 2trtog? 

It’s says to decrease every third line but I can’t get the maths to work from it being 104 groups to 68 groups. 

 

Any thoughts appreciated! Thankyou very much! 

[Granny Square]

I'm reading this as a single 2trtog, in other words half of a 'v' stitch which is tr2tog, chain x, tr2tog.  That makes a subtle decrease which is visible, but subtle, so I think you are doing it right.

I think this bears sketching out/diagramming a 'pie shape' of the area between 2 decreases [not diagramming the whole piece] rather than trying to do the math, since you are keeping the decreases in a line above each other, the 'decrease lines' will get closer together each round toward the top of the piece.  The # of decreases will be the same each decrease row, but the # of stitches between will lessen.