Confused with instructions for cardigan

I am working on a cardigan pattern. I have cast on 51 stitches and worked 3 rows in 1 x 1 rib. Now the pattern says:

4th row: Rib 11, rib2tog, (rib 5, rib2tog)5 times, rib 3. 45 sts.

Is Rib 11=22 sts?

No not 22 stitches, just 11 stitches.

rib 11 means do the ribbing pattern (i.e k1 p1 or k2 p2 whatever you ahve established as the pattern) over 11 stitches
that means if you were on k1 p1 you would do:

When in doubt, and since you have the stitch count, you can always count it out both ways and see which one works. In this case, 11 sts adds up to the correct count of 45, whereas with the 22 sts you’d end up with 56. That’s 5 stitches MORE than what you have on your needle