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VTMO 2020 — Grade 8 — vtmo Question 7

VTMO · VTMO 2020 — Grade 8 — vtmo

Question 7

Among plates $0001 , \ldots , 9999$, how many have equal left-pair and right-pair digit sums?
  1. $661$
  2. $665$
  3. $667$
  4. $668$
  5. $669$