A blackboard with the sum 1-1= written on it in white chalk.

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Images of chalk words on a blackboard.

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Size: 4200px × 2800px
Location: London, Ontario, Canada.
Photo credit: © Jonny White / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 1-1=, blackboard, chalk, learn, mathematics, subtract, subtraction, word, written