Răspuns:
Explicație pas cu pas:
a)
[tex] \frac{a}{7} = \frac{11}{b} \\ [/tex]
[tex]a \times b = 7 \times 11 = \boxed{77}[/tex]
b)
[tex] \frac{a}{8} = \frac{5}{b} \\ [/tex]
[tex]a \times b = 8 \times 5 = \boxed{40}[/tex]
c)
[tex] \frac{a}{0,(3)} = \frac{15}{b} \\ [/tex]
[tex]a \times b = 15 \times 0,(3) = 15 \times \frac{3}{9} = \frac{45}{9} = \boxed{5} \\ [/tex]
d)
[tex] \frac{a}{20} = \frac{0,3(6)}{9} \\ [/tex]
[tex]a = \frac{0,3(6) \times 20}{9} = \frac{ \frac{36 - 3}{90} \times 20 }{9} = \frac{ \frac{ 33^{(3}}{90} \times 20 }{9} \\ [/tex]
[tex] = \frac{ \frac{11}{30} \times 20}{9} = \frac{ \frac{220}{30} }{9} = \frac{220}{30} \times \frac{1}{9} = \frac{ 220^{(10}}{270} = \boxed{\frac{22}{27}} \\ [/tex]
