Răspuns :
a). 78 - 39 + 11 = 39 + 11 = 50
b). 78 - 39 + 42 = 39 + 42 = 81
c). 78 - 39 + 17 = 39 + 17 = 56
d). 78 - 39 + ( 20 + 27 ) = 39 + 47 = 86
e). 78 - 39 + ( 100 - 55 ) = 39 + 45 = 84
a). 78 - 39 + 11 = 39 + 11 = 50
b). 78 - 39 + 42 = 39 + 42 = 81
c). 78 - 39 + 17 = 39 + 17 = 56
d). 78 - 39 + ( 20 + 27 ) = 39 + 47 = 86
e). 78 - 39 + ( 100 - 55 ) = 39 + 45 = 84