Răspuns :
a) - 9/20 + 11/18 - 5/24 + 7/12 = - 162/360 + 220/360 - 75/360 + 210/360 = 193/360
b) 1 si 7/12 + [- 5/18 - 7/24] = 19/12 + [- 12/72 - 21/72] = 19/12 - 33/72 = 114/72 - 33/72 = 81/72 = 9/8 = 1 si 1/8
b) 1 si 7/12 + [- 5/18 - 7/24] = 19/12 + [- 12/72 - 21/72] = 19/12 - 33/72 = 114/72 - 33/72 = 81/72 = 9/8 = 1 si 1/8
-9/20 +(-5/24)+7/12.
Inmultim fiecare fractie incat sa fie numitorul 120, prima fractie cu inmultim cu 6, a doua cu 5 si ultima cu 10
-54-25+70=-9
b)-5/12+(-20-21)/72
-5/12-41/72
-30-41=-71