1. a)[tex] \frac{1}{4} [/tex]+[tex] \frac{5}{6} [/tex]+[tex] \frac{7}{12} [/tex]=[tex] \frac{3+10+7}{12} [/tex]=[tex] \frac{20}{12} [/tex]=[tex] \frac{5}{3} [/tex] (am simplificat cu 4)
b)[tex] \frac{5}{36} - \frac{1}{12}- \frac{1}{18} = \frac{5-3-2}{36} = \frac{0}{36} =0 [/tex]
2)[tex] \frac{1}{2} *3*5+ \frac{1}{3} *5*7+ \frac{1}{2} *5*7= \frac{15}{2} + \frac{35}{3} + \frac{35}{2} = \frac{45+70+105}{6} = \frac{220}{6} = \frac{110}{3} [/tex]
