решите пожалуйста, 7 / 8*y = 1   1 / 4; 5/9x =1  1/3

7/8у = 1 1/4                                        5/9х = 1 1/3

7/8у = 5/4                                           5/9х = 4/3 

8у * 5 = 7 * 4                                      9х * 4 = 5 * 3

40у = 28                                             36х = 15

у = 28 : 40                                          х = 15 : 36

у = 0,7                                                х = 5/12

Проверка:                                          Проверка:                          

7 : (8 * 0,7) = 1 1/4                             5 : (9 * 5/12) = 1 1/3

7 : 5,6 = 5 : 4                                      5 * 12/45 = 1 1/3 

1,25 = 1,25                                         12/9 = 4/3

                                                           1 1/3 = 1 1/3