#4 и 5 пж пж пж аааа

4/495    -  13/825 = 20/2475  - 39/2475 = - 19/2475 (7/16  +  5/12) * 1  7/41  + 1  1/39 :(4/13 - 20/39)= - 4 1) 7/16 + 5/12= 21/48  + 20/48 = 41/48 2) 4/13  - 20/39 =  12/39   -20/39= -8/39 3) 41/48   *   1  7/41 = 41/48   *   48/41 = 1 4)  1  1/39   :  (-8/39) =   40/39    *  (- 39/8) = - 40/8= -5 5) 1 + (-5) = -4