3. 112(1×53+32×1-1+45×84)=
= 112(53+32-1+45×84)
= 112(53+32-1+3780)
= 112(85-1+3780)
= 112(84+3780)
= 112×3864
= 432768
4. Notam numerele a si b
1) a-b=51
2)a÷b=2 rest 20 => a=b×2+20
b×2+20-b=51
2b+20-b=51
b+20=51
b=51-20 => b=31
b=31 => a=51+31
a=82
