Revision crossword

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Across
  1. 3. You do this to an equation to find the value of the letters (5 letters)
  2. 4. Divide by this number to find a quarter of something (4 letters)
  3. 6. An average found by finding the middle (6 letters)
  4. 7. The order of operations (6 letters)
  5. 9. The total length around a shape's exterior (9 letters)
Down
  1. 1. A triangle with no equal length sides and no equal angles (7 letters)
  2. 2. There are 1000 of these in a kilogram (5 letters)
  3. 3. A shape with four equal angles and four equal sides (6 letters)
  4. 5. The angles in this shape add up to 180 degrees (8 letters)
  5. 8. Means the same as over 100 (7 letters)