Work challenge!

Bring on the work challenge. We are starting a weight loss challenge at work today. I'm hoping this will be the push I need. Weigh in this morning I was at 182 on the work scales...these CANNOT be the same as my home scale...I really hope. Challenge is to whomever loses the biggest percent if weight by then end of 8 weeks. My goal is 20 lbs. Hopefully I'm not too optimistic.