I got a 48 or 49 (how embarrassing, I already can't remember) and I don't recall having any stats questions. I had stats in college and did really well, but clearly nothing stuck because I gave up studying for these in my practice. I as a general rule don't memorize anything (I didn't study any formulas for GMAT), and without a formula in front of me, these made my head spin. So I decided to play the odds and if that had brought my score down, so be it.
They obviously didn't make a lasting impression, so either I didn't have one or it was really easy. If you can do the easy ones, I would recommend ditching the rest.
"Egotism is the anesthetic that dulls the pain of stupidity." - Frank Leahy
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