Decrease every 10th row?

Hi all, quick pattern question. The pattern says… (I’m making the Large, so it’s the 10th row, 8 times, for a total of 9 decrease rows).

“Row 6 : Work “decrease row” this and every 9th (12th, 10th, 12th) row 9 (6, 8, 7) times. *
*(For a total of 10(7, 9, 8) decrease rows in all)”

Now, my question is…

Should there be 9 rows between each decrease row, or 10? Like, Row 6 is decrease, then I start counting until I get to row 10 and that’s the decrease row, or after the 10th row?

The reason I ask (so you don’t think I’m just dumb), is that it tells how to decrease for RS rows and WS rows. But, if I decrease when there are 9 rows between the decrease rows, they all end up being RS rows!

I just don’t want to make a mess!

Thanks in advance!

9 rows between. Dec on row 6, the next dec is row 16. The tell you how to dec for the WS rows because the smallest size decreases every 9th row, so sometimes the dec will be RS, sometimes WS for that size.