math-nli: Output if sentence 2 Entails statement 1 or Contradicts statement 1 - 
sentence 1: Margaret had some Watch. Crystal gave him 7 more. Now Margaret has 14 Watch. 
sentence 2:  Margaret had 6 Watch at first.
<equate> (14 - 7, 6)
Margaret had some Watch. Crystal gave him 7 more. Now Margaret has 14 Watch. 
 Margaret had 6 Watch at first.