\(A=1.\left(12+13+14+15+16\right)\)
\(A=1.70\)
\(A=70\)
\(A=\left(1+12\right).\left(1+13\right).\left(1+14\right).\left(1+15\right).\left(1+16\right)\\ =1.\left(12+13+14+15+16\right)\\ =1.70\\ =70\)
A= (1+12).(1+13).(1+14).(1+15).( 1+16 )
A= 1.70
A= 70