Science's most important (and controversial) number has its origins in a British experiment involving milk and tea.

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PRODUCTION CREDITS

Digital Producer: Ana Aceves

PREDICTION BY THE NUMBERS

Written, Produced, and Directed by: Daniel McCabe

Co-Producer: Cara Feinberg

© WGBH Educational Foundation 2018

MEDIA CREDITS

Imagery: Alamy Getty Pond5 Science Photo Library Shutterstock

Music: ­APM