Выполни  действия:8/9-7/1217/20-5/127/15-3/2011/12-7/15

1) [latex] \frac{8}{9}- \frac{7}{12}= \frac{8*4-7*3}{36}= \frac{11}{36} [/latex] 2) [latex] \frac{17}{20}- \frac{5}{12}= \frac{17*3-5*5}{60} = \frac{26}{60}= \frac{13}{30} [/latex] 3) [latex] \frac{7}{15}- \frac{3}{20}= \frac{7*4-3*3}{60} = \frac{19}{60} [/latex] 4) [latex]\frac{11}{12}- \frac{7}{15}=\frac{11*5-7*4}{60}= \frac{27}{60}[/latex]