Answers

2014-12-17T20:49:31+05:30
 31/63 - 5/7 (Taking LCM as 63)
= 31-45/63
= -14/63
0
2014-12-17T21:07:52+05:30
   31/63 - 5/7
=  (31-5*9)/63
=  (31-45)/63
=  -14/63 = -2/9
0
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