math crossword

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Across
  1. 3. Distance around a shape
  2. 4. Result of addition
  3. 5. Comparison of two numbers
  4. 6. Part of a whole
  5. 7. Line through circle’s center
  6. 9. Middle number in a data set
Down
  1. 1. Longest side of a right triangle
  2. 2. Unknown value in algebra
  3. 4. Shape with four equal sides
  4. 8. Space inside a shape