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