4.
[tex]a) \ \frac{1}{7}+2,5+\frac{6}{7} = \frac{1}{7}+\frac{6}{7}+2,5 = \frac{7}{7}+2,5 = 1+2,5 = 3,5\\\\b) \ 0,25+1\frac{7}{8}+0,75 = 0,25+0,75+1\frac{7}{8} = 1+1\frac{7}{8} = 2\frac{7}{8}\\\\c) \ 32,8 + 2,79 + (-0,8) = 32,8 + (-8) + 2,79 = 32+2,79 = 34,79[/tex]
5.
[tex]a) \ 4\frac{2}{3}\cdot\frac{9}{10}\cdot\frac{3}{14} = \frac{14}{3}\cdot\frac{3}{14}\cdot\frac{9}{10} = 1\cdot\frac{9}{10} = \frac{9}{10}\\\\b) \ \frac{\pi}{13}\cdot3\frac{1}{3}\cdot\frac{0,13}{2} = \frac{\pi}{13}\cdot\frac{10}{3}\cdot\frac{13}{200}=\frac{\pi}{13}\cdot\frac{13}{200}\cdot\frac{10}{3} =\frac{\pi}{60}[/tex]
[tex]c) \ -1\frac{3}{7}\cdot2\frac{3}{4}\cdot\frac{7}{10}\cdot4=-\frac{10}{7}\cdot\frac{11}{4}\cdot\frac{7}{10}\cdot4=-\frac{10}{7}\cdot\frac{7}{10}\cdot\frac{11}{4}\cdot4 = -1\cdot11 = -11[/tex]
