Question

2+7=34
8+9=18
6+3=76
5+7=?

Answer 1

2 + 7 = ( 2 X 10 ) + ( 2 X 7 ) = 34 
8 + 9 = ( 9 X 10 ) - ( 9 X 8 ) = 18
6 + 3 = ( 6 X 10 ) + ( 6 X 3 ) = 78
Hence 
5 + 7 = ( 7 x 10 ) - ( 7 x 5 ) = 35

Answer 2

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