Words Related to Addition

123456789
Across
  1. 2. in _ll
  2. 3. i _ c r _ _ s e
  3. 5. b _ t h
  4. 6. c _ m _ _ n e
  5. 8. t _ _ a l
  6. 9. m _ _ e
Down
  1. 1. a _ t o _ _ t h e r
  2. 4. s _ m
  3. 7. p _ _ s