\[(12.3+1.68)\cdot2.05-0.348:2.9\]
\[12.3+1.68=13.98,\qquad 13.98\cdot2.05=28.659\]
\[0.348:2.9=0.12\]
\[28.659-0.12=28.539\]
Ответ: 28,539.