They got stuck on a broken-down bus, but married clowns Dave and Cherie Gregg were ultimately undone on The Amazing Race by... math. Tasked with calculating the average weight of a head of cattle in a pen using long division, Dave got so stuck that the cattle were eventually cleared out. "Not in a million years [did I think we would be eliminated because of math]! Not in $1 million even!" he tells TVGuide.com. Why couldn't he figure it out? And what happened to their bus? Find out below.