Условие:

87 − (37 + 50);
69 − (4646);
39 + (5950);
44 − (2016);
70 + (15 + 15);
70 − (1515);
63 + (17 + 0);
63 − (0 + 13).

87 − (37 + 50) = 87 − (7 + 30 + 50) = 87 − (7 + 80) = 8787 = 0
 
69 − (4646) = 690 = 69
 
39 + (5950) = 39 + (5050 + 9) = 39 + 9 = 39 + 1 + 8 = 40 + 8 = 48
 
44 − (2016) = 444 = 40
 
70 + (15 + 15) = 70 + 30 = 100
 
70 − (1515) = 700 = 70
 
63 + (17 + 0) = 63 + 17 = (60 + 10) + (3 + 7) = 70 + 10 = 80
 
63 − (0 + 13) = 6313 = 50