Recently, I asked the BuzzFeed Community for their best math trick. I'm not talking quantum physics here, but just, you know, an easy way to figure out how much butter I need if I'm doubling a recipe.

2. "I tried the 'hack' where you walk into a hotel, and tell the receptionist that you left a phone charger in your room, so you get a spare for free." "When they asked me what my name was and what ...