Предмет: Математика, автор: fejlnibro

Помогите решить 317 и 318

Приложения:

Ответы

Автор ответа: nktselepov

317)

$\displaystyle\bigg(17 \frac{3}{4} +16\frac{3}{5}\bigg) -\bigg( 29\frac{5}{8} -14\frac{7}{10} \bigg)=\bigg( \frac{71}{4} +\frac{81}{5}\bigg) -\bigg(\frac{237}{8} -\frac{147}{10} \bigg)=\\\\=\frac{679}{20} -\frac{597}{40}=\frac{1358-597}{40} =\frac{761}{40}=19\frac{1}{40}$

318)

$\displaystyle\bigg(x-7\frac{1}{6}\bigg)+7\frac{7}{18} =5\frac{1}{9} \\\\\bigg(x-\frac{43}{6}\bigg)+\frac{133}{18} =\frac{46}{9}\\\\\bigg(x-\frac{129}{18}\bigg)+\frac{133}{18} =\frac{92}{18}\\\\x-\frac{129}{18}=-\frac{41}{18} \\\\x=\frac{88}{18} =4\frac{16}{18} =4\frac{8}{9}$

$\displaystyle 9\frac{11}{15} -\bigg(x+2\frac{1}{10}\bigg) =3\frac{17}{20} \\\\\frac{146}{15} -\bigg(x+\frac{21}{10}\bigg)=\frac{77}{20} \\\\\frac{584}{60} -\bigg(x+\frac{126}{60} \bigg)=\frac{231}{60} \\\\-x-\frac{126}{60} =-\frac{353}{60} \\\\-x=-\frac{227}{60} \\\\x=\frac{227}{60}=3\frac{47}{60}$