math-nli: Output if sentence 2 Entails statement 1 or Contradicts statement 1 - 
sentence 1: Robert had 152 blackcurrant. Jane gripped some blackcurrant. Now Robert has 71  blackcurrant. 
sentence 2:  Jane gripped 81 blackcurrants.
<equate> (152 - 71, 81)
Robert had 152 blackcurrant. Jane gripped some blackcurrant. Now Robert has 71  blackcurrant. 
 Jane gripped 81 blackcurrants.