Question

:1)11целых7/9+у=13целых1/18; 2)60целых2/5-у=57целых3/4; 3)1целая13/75×у=2/3; 4)24/35÷у=1целая5/49.

Answer 1

1)  $11\dfrac{7}{9}+y=13\dfrac{1}{18}\\\\ y=\dfrac{235}{18}-\dfrac{106}{9}\\\\y=\dfrac{235}{18}-\dfrac{212}{18}\\\\ y=\dfrac{23}{18}\\\\ y=1\dfrac{5}{18}$2)

$60\dfrac{2}{5}-y=57\dfrac{3}{4}\\\\ -y=\dfrac{231}{4}-\dfrac{302}{5}\\\\ -y=\dfrac{1155}{20}-\dfrac{1208}{20}\\\\ -y=\dfrac{-53}{20}\\\\ y=\dfrac{53}{20}\\\\ y=2\dfrac{13}{20}$

3)

$1\dfrac{13}{75}\cdot y=\dfrac{2}{3}\\\\ y=\dfrac{2}{3}\div\dfrac{88}{75}\\\\ y=\dfrac{2}{3}\cdot\dfrac{75}{88}\\\\ y=\dfrac{1}{1}\cdot\dfrac{25}{44}\\\\ y=\dfrac{25}{44}$

4)

$\dfrac{24}{35}\div y=1\dfrac{5}{49}\\\\ \dfrac{24}{35}\div\dfrac{54}{49}=y\\\\ y=\dfrac{24}{35}\cdot\dfrac{49}{54}\\\\y=\dfrac{12}{5}\cdot\dfrac{7}{27}\\\\y=\dfrac{4}{5}\cdot\dfrac{7}{9}\\\\ y=\dfrac{28}{45}$