An engineer, a chemist and a statistician are staying in a hotel. (It’s a triple room, very cosy.) The first night they are there, a fire breaks out and wakes them up. The engineer gets up, grabs the fire extinguisher and puts out the fire. Later, they’re all woken by another fire (very dodgy health and safety). The chemist thinks “the fire reaction requires oxygen”, grabs a fire blanket and smothers the flames until they go out. Even later, the engineer and the chemist are woken by the statistician lighting a series of fires in the corner. “What are you doing?”, they cry in unison.