I’m so full of questions! 
I’ve been working on my sleeve and I’ve come to a line that says
K10, k2tog across, 3 stitches decreased
For me this means that if you knit ten then knit two together you’ve have decreased by 3 stitches…which won’t be the case for me…
I started with 42 stitches and then knitted for 41/2 inches decreasing by 2 every 6th row…I did this 3 times leaving me with 36
just some more info
thank you so much for any help given