1)
[tex]3\frac{1}{4}+2,5=3\frac{25}{100}+2,5=3,25+2,5=5,75\\[/tex]
2)
[tex]4,9-1\frac{3}{5}=4,9-1\frac{6}{10}=4,9-1,6=3,3\\[/tex]
3)
[tex]8,25-4\frac{1}{2}=8,25-4\frac{5}{10}=8,25-4,5=3,75\\[/tex]
4)
[tex]4\frac{1}{8}+5,45=4\frac{125}{1000}+5,45=4,125+5,45=9,565\\[/tex]
5)
[tex]3\frac{2}{3}+4,25=3\frac{2}{3}+4\frac{25}{100}=3\frac{2}{3}+4\frac{1}{4}=3\frac{8}{12}+4\frac{3}{12}=7\frac{11}{12}\\[/tex]
6)
[tex]6,4-2\frac{1}{9}=6\frac{4}{10}-2\frac{1}{9}=6\frac{2}{5}-2\frac{1}{9}=6\frac{18}{45}-2\frac{5}{45}=4\frac{13}{45}\\[/tex]
7)
[tex]3,5:2\frac{1}{3}=3\frac{5}{10}:\frac{7}{3}=3\frac{1}{2}:\frac{7}{3}=\frac{\not7^1}{2}\cdot\frac{3}{\not7_1}=\frac{3}{2}=1\frac{1}{2}\\[/tex]
8)
[tex]2,4\cdot3\frac{3}{4}=2\frac{2}{5}\cdot\frac{15}{4}=\frac{\not12^3}{\not5_1}\cdot\frac{\not15^3}{\not4_1}=9[/tex]
9)
[tex]2\frac{1}{2}\cdot1,5=\frac{5}{2}\cdot1\frac{1}{2}=\frac{5}{2}\cdot\frac{3}{2}=\frac{15}{4}=3\frac{3}{4}\\[/tex]
10)
[tex]2,125:1\frac{1}{4}=2\frac{125}{1000}:\frac{5}{4}=2\frac{1}{8}\cdot\frac{4}{5}=\frac{17}{\not8_2}\cdot\frac{\not4^1}{5}=\frac{17}{10}=1\frac{7}{10}\\[/tex]
11)
[tex](1,6-\frac{3}{5}+0,25)\cdot2=(1,6-\frac{6}{10}+0,25)\cdot2=\\\\=(1,6-0,6+0,25)\cdot2=(1+0,25)\cdot2=1,25\cdot2=2,5[/tex]
