Thank you both. I now understand how I am getting the 10 stitches.
But I'm still confused about one of the rounds;
Round 1: Cast on 5 stitches,
Round 2: knit around. Place a marker to mark the beginning of the round.
Round 3: Next round, make 1 stitch in each stitch (10 stitches).
This is where I am confused...LOL...at least I think. Where am I missing the round. Is it earlier in the instructions?
Round 5: k1, yo around to marker. (20 stitches).