Boy, glasses, slide rules, head, rest on, portrait, schoolboy, young person, 13 years, grinds, abaci, concentration, concentrate, count, work out, add, addition, subtraction, subtract, think below, plus, sum, consider, teasers, school, learn, continuing education, circular frame, studio

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Size: 3629px × 5443px
Photo credit: © Hans-Peter Merten / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 13, abaci, add, addition, boy, circular, concentrate, concentration, continuing, count, education, frame, glasses, grinds, head, learn, person, portrait, rest, rules, school, schoolboy, slide, studio, subtract, subtraction, sum, teasers, work, years, young