Integer puzzle

Edit Answers
12345678910111213141516171819
Across
  1. 1. 15 + 15
  2. 4. 20 x 3
  3. 8. 10 + 6
  4. 9. 20 - 2
  5. 11. -4 x -3
  6. 13. 10 + 0
  7. 14. -1 + 2
  8. 16. 18 + -9
  9. 17. -10 + 10
  10. 19. 5 - -8
Down
  1. 2. 30 - 10
  2. 3. -2 + 7
  3. 5. 6 divided by 2
  4. 6. 30 divided by 2
  5. 7. 3 - -4
  6. 9. 22 + -11
  7. 10. -10 divided by -5
  8. 12. 4 x 2
  9. 15. 2 + 2
  10. 18. 3 + 3