MADHU=In alphabet M at 13th place ans A at 1st place and D at 4th place , H at 8th place, U at 21.add A and U = 1 +21=22and add M, D and H= 13+4+8=25.now Subtract them and the result is 3.and for NISHA Nat 14place, I at 9 place, S at 19 place, Hat 8 place, Aat 1 place now add I and A=1+9=10 now add N, S and H =9+19+8=41.now Subtract them 41-10=31ans.