7 + 6 = 7 + ( 3 + 3 ) 10
= ( 7 + 3 ) + 3 + 3
= 10 + 3 1 3
27 + 5 = 27 + ( 3 + 2 ) 30
= (27 + 3 ) + 2 + 2
= 30 + 2 32