Addition Subtraction cross number puzzle

12345678
Across
  1. 3. 32+68
  2. 4. 573+427
  3. 6. 194+6
  4. 7. 946-46
  5. 8. 372-72
Down
  1. 1. 450+250
  2. 2. 500-250
  3. 3. 750+250
  4. 5. 1981-81
  5. 6. 30-10
  6. 8. 100-64