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Дефиниција, особине, решени задаци.

Задаци

Текст задатака објашњених у видео лекцији:

Пр.1)   Израчунати:

           а) $\frac{1}{5} + \frac{3}{5}$

           б) $\frac{3}{7} + \frac{2}{7}$

           в) $\frac{5}{{11}} + \frac{6}{{11}}$

           г) $1\frac{1}{3} + 2\frac{1}{3}$

           д) $2\frac{3}{8} + 1\frac{7}{8}$

Пр.2)   Израчунати:

           а) $\frac{1}{2} + \frac{1}{6}$

           б) $\frac{1}{3} + \frac{1}{2}$

           в) $\frac{5}{8} + \frac{5}{6}$

           г) $2 + \frac{1}{3}$

           д) $2\frac{1}{4} + 3\frac{1}{6}$

           ђ) $1\frac{3}{5} + 3\frac{1}{2}$

           е) $\frac{1}{3} + \frac{1}{2} + \frac{1}{4}$

           ж) $\frac{1}{8} + \frac{5}{6} + \frac{1}{2}$

           з) $2 + \frac{1}{3} + 3\frac{5}{6}$
           и) $3\frac{4}{5} + 2\frac{5}{6} + 1\frac{9}{{10}}$

 

 

Пр.1)  а) $\frac{1}{5} + \frac{3}{5} = \frac{{1 + 5}}{5} = \frac{4}{5}$

           б) $\frac{3}{7} + \frac{2}{7} = \frac{{3 + 2}}{7} = \frac{5}{7}$

           в) $\frac{5}{{11}} + \frac{6}{{11}} = \frac{{5 + 6}}{{11}} = \frac{{11}}{{11}} = 1$

           г) $1\frac{1}{3} + 2\frac{1}{3} = \frac{4}{3} + \frac{7}{3} = \frac{{11}}{3} = 3\frac{2}{3}$

           д) $1\frac{1}{3} + 2\frac{1}{3} = \frac{4}{3} + \frac{7}{3} = \frac{{11}}{3} = 3\frac{2}{3}$

 

Пр.2)  а) $\frac{1}{2} + \frac{1}{6} = \frac{3}{6} + \frac{1}{6} = \frac{4}{6} = \frac{2}{3}$

           б) $\frac{1}{3} + \frac{1}{2} = \frac{2}{6} + \frac{3}{6} = \frac{5}{6}$

           в) $\frac{5}{8} + \frac{5}{6} = \frac{{15}}{{24}} + \frac{{20}}{{24}} = \frac{{35}}{{24}} = 1\frac{{11}}{{24}}$

           г) $2 + \frac{1}{3} = 2\frac{1}{3}$

           д) $2\frac{1}{4} + 3\frac{1}{6} = 2\frac{3}{{12}} + 3\frac{2}{{12}} = 5\frac{5}{{12}}$

           ђ) $1\frac{3}{5} + 3\frac{1}{2} = 1\frac{6}{{10}} + 3\frac{5}{{10}} = 4\frac{{11}}{{10}} = 5\frac{1}{{10}}$

           е) $\frac{1}{3} + \frac{1}{2} + \frac{1}{4} = \frac{2}{6} + \frac{3}{6} + \frac{1}{4} = \frac{5}{6} + \frac{1}{4} = \frac{{10}}{{12}} + \frac{3}{{12}} = \frac{{13}}{{12}} = 1\frac{1}{{12}}$

           ж) $\frac{1}{8} + \frac{5}{6} + \frac{1}{2} = \frac{3}{{24}} + \frac{{20}}{{24}} + \frac{{12}}{{24}} = \frac{{3 + 20 + 12}}{{24}} = \frac{{35}}{{24}} = 1\frac{{11}}{{24}}$

           з) $2 + \frac{1}{3} + 3\frac{5}{6} = 2\frac{1}{3} + 3\frac{5}{6} = 2\frac{2}{6} + 3\frac{5}{6} = 5\frac{7}{6} = 6\frac{1}{6}$
           и) $3\frac{4}{5} + 2\frac{5}{6} + 1\frac{9}{{10}} = 3\frac{{24}}{{30}} + 2\frac{{25}}{{30}} + 1\frac{{27}}{{30}} = 6\frac{{76}}{{30}} = 8\frac{{16}}{{30}} = 8\frac{8}{{15}}$