pi number handwritten on isolated vintage blackboard

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Size: 5766px × 3844px
Photo credit: © Yury Zap / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: blackboard, circle, circumference, constant, definition, diameter, divided, education, exact, frame, handwritten, isolated, knowledge, mathematical, mathematics, measure, number, pi, principle, red, school, science, vintage