\[b_{1} = 3;\ \ \ b_{4} = - 192.\]
\[3;\ \ b_{1}q;\ \ b_{1}q^{2};\ - 192\]
\[3q^{3} = - 192\]
\[q^{3} = - 64\]
\[q = - 4.\]
\[b_{1}q = 3 \cdot ( - 4) = - 12;\]
\[b_{1}q^{2} = 3 \cdot ( - 4)^{2} = 3 \cdot 16 = 48.\]
\[Ответ:\ \ числа\ - 12;48.\]