Question

Алла щезла зрубали шкз​

Answer 1

$\frac{1}{4}+\frac{9}{20}-0,7=\frac{1}{4}+\frac{9}{20}-\frac{7}{10}=\frac{1*5}{4*5}+\frac{9}{20}-\frac{7*2}{10*2}=\frac{5}{20}+\frac{9}{20}-\frac{14}{20}=\frac{5+9-14}{20}=\frac{0}{20}=0$