Условие:

90 − (4640);
10 + (599);
28 + 6 + 54;
90798;
0 + 9;
0 + 0.

90 − (4640) = 906 = 84;
10 + (599) = 10 + 50 = 60;
28 + 6 + 54 = 28 + 60 = 88;
90798 = 118 = 3;
0 + 9 = 9;
0 + 0 = 0.