Really? I distinctly remembering mine had 2 that were 15+ and one that had 22 paragraphs. The 22 paragraph one had shorter paragraphs though.
The test usually has one short-ish passage and 2 long ones or 2 medium length passages and one long one. Shoot for completing shorter ones in 16 minutes. 18-20 minutes for the medium and long ones. Hopefully the extra 4-6 minutes you have remaining can be used if you are getting too much trouble from any particular passage.