Question

Номер 6, помогите пожалуйста ​

Answer 1

$\frac{11}{77 } = \frac{1}{7 } \\ \\ \frac{7}{77} = \frac{1}{11 } \\ \\ \frac{77}{77} = 1$

$\frac{c}{39} = \frac{8}{13} \\ \\ 13c = 156 \\ c = 156 \div 13 \\ c = 12$

$\frac{7}{9} = \frac{49}{c} \\ 7c = 441 \\ c = 441 \div 7 \\ c = 63$