x=1 y=2,3,4 ,5 ,6,7,8,9
x=2 y=1,3,.............9
x=3 y=1,2,4...........9 daca x diferit de y
a=nr.
a+a+1+a+2+a+3=18
4a=12
a=3, nr sunt:
3456=18 consec. cresc.
6543=18 consec. descr.
3) =(84+60x100:20-14):[(40-40)+65-28]=(84+60x5-14):(0+37)=(84+300-14):37=370:37=10
4)= 312+(2500:25)+(3690:3)=1642
312+100+1230=1642
1642=1642
5) = 4750:[16+(23x3)-(17+41)+50-72]-123=827
4750:[16+69-58+50-72]-123=827
4750:[85-58+50-72]-123=827
4750:[27+50-72]-123=827
4750:[77-72]-123=827
4750:5-123=827
900-123=827
827=827