30++20=70 27+40+ =78 97-50-=28
-25-15=36 52+-11=45 76--7=53
45+375 18+1927 16+27+4386
82-532 75-3639 58-(27-14) 17
90-54= 38+44= 8+57=
60-27-9= 91-(42+19)= 6+52-26=
1,3,2,6,4,9,8,,,15,,18,……