Question

помогите СРОЧНО РЕШИТЬ! ДАМ МНОГО БАЛОВ!!!!!​

Answer 1

б)

$\frac{x-1}{4,2} = \frac{15}{6,3}\\6,3(x-1) = 4,2*15\\6,3x - 6,3= 63\\6,3x=63+6,3\\6,3x = 69,3\\x = 11$

Ответ: 11.

в)

$1\frac{2}{5} : \frac{5}{6} = 1,68:x\\\frac{7}{5} : \frac{5}{6} =\frac{168}{100x} \\\\\frac{7*6}{5*5} =\frac{168}{100x}\\\frac{42}{25} =\frac{168}{100x}\\100x * 42=25*168\\100x = \frac{25*168}{42} \\100x=100\\x = 1$

Ответ: 1.