Mathematician's crossword

123456789101112131415
Across
  1. 1. The area of a triangle whose b=9 and h=8.
  2. 3. The answer of a*b when a=(8*3)/4 and b=(18/6)*3
  3. 5. The number of faces a quadrilateral, pentagon, hexagon, decahedron and a dodecahedron has, when combined together.
  4. 7. The dates of valentines day and Christmas added together(including the month number at the front)
  5. 8. The fifteenth factor in the 12 times table.
  6. 9. The speed limit in Brunei*5 and then multiplied by 2.5.
  7. 10. The number of books 15 trilogies has.
  8. 11. A number that can never be determined to be even or odd.
  9. 12. The answer is the value of X(In degrees) when a circle is divided into 4 parts, 3 of them being X and one of them being Y.Y=210.
  10. 14. The degrees a perpendicular bisector represents.
  11. 15. The number of stars the American flag has.
Down
  1. 2. The answer of what 5 squared multiplied by 5 squared is.
  2. 4. The number of months multiplied by the number of days in a leap year.
  3. 6. The number of times it's not possible to fold a piece of paper in half continuously.
  4. 7. The sum of 123456789 and 876543211.
  5. 9. The fifth triangular number in the sequence.
  6. 10. The number of leaves 12 lucky clovers have, altogether.
  7. 12. Solve this equation that is written using roman numerals: C-XXXI+LIX. Answer in modern numbers, NOT roman numerals.
  8. 13. The number of vertices a square-based pyramid has.