Cross-Number Puzzle using +/-

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Across
  1. 1. Eleven added to nine
  2. 3. Subtract twelve from thirty
  3. 5. Six and five combined
  4. 7. The difference of twenty‑two and eight
  5. 10. The total of fourteen and six
  6. 16. Eighteen increased by seven
  7. 17. Twenty minus five
  8. 18. Seven together with six
  9. 19. Forty‑five left after twenty
  10. 20. Twenty‑seven less nine
Down
  1. 2. Sixteen remain altogether after four
  2. 4. The sum of twelve and eight
  3. 6. Fourteen decreased by six
  4. 8. Twenty‑five with ten fewer
  5. 9. Add nine and four
  6. 11. Fifteen taken away from forty
  7. 12. Thirty change by seven
  8. 13. Eight and twelve in all make twenty
  9. 14. Five plus three
  10. 15. How many more than seven is thirteen