Explicație pas cu pas:
1.
[tex] \frac{1}{5} ; \frac{2}{5} ; \frac{3}{5} ; \frac{4}{5} [/tex]
2.
[tex] \frac{3}{2} = \frac{6}{4} [/tex]
[tex] \frac{6}{3} = \frac{1}{2} [/tex]
[tex]\frac{2}{2} = \frac{3}{3} = \frac{6}{6} [/tex]
[tex]\frac{2}{4} = \frac{3}{6} = \frac{4}{18} = \frac{5}{10} [/tex]
3.
[tex] \frac{9}{9} ;\frac{7}{9} ;\frac{6}{9} ;\frac{4}{9} ;\frac{3}{9} ;\frac{1}{9}[/tex]
4.
[tex]a. \frac{3}{4} \: \: ;b. \frac{7}{9} \: \: ;c. \frac{8}{10}[/tex]
5.
[tex]3 + a < 8 \\ a < 8 - 3 \\ a < 5[/tex]
[tex]b - 3 < 5 \\ b < 5 + 3 \\ b < 8[/tex]
[tex]c + c < 7 \\ c = 1;c = 2;c = 3[/tex]
6.
[tex]\frac{a}{3} = \frac{b}{7} = 9 \\ \frac{a}{3} = 9 = > a = 9 \times 3 = > a = 27\\ \frac{b}{7} = 9 = > b = 9 \times 7 = > b = 63 \\ a + b = 27 + 63 = 90[/tex]
sau
[tex]\frac{a}{3} = \frac{b}{7} = \frac{9}{1} = \frac{a + b + 9}{3 + 7 + 1} = \frac{a + b + 9}{11} \\ \frac{a + b + 9}{11} = 9 \\ a + b + 9 = 9 \times 11 \\ a + b + 9 = 99 \\ a + b = 99 - 9 \\a + b = 90 [/tex]
