29.2% (w/W) HCI stock solution has density of 1.25 g mL^-1. The molecular weight of HCI is 36.5 mol^-1. The volume (mL) of stock solution required to prepare a 200 mL solution 0.4 M HCI is

Mass of HCl in 1.0 mL stock solution $=1.25\times \frac{29.2}{100}=0.365\mathrm{g}$
Mass of HCI required for 200 mL solution of 0.4 M HCI $=\frac{200}{1000}\times 0.4\times 36.5=0.08\times 36.5\mathrm{g}$
$\begin{array}{l}\because 0.365\mathrm{g}\text{ of }\mathrm{HCl}\text{ is present in }1.0\mathrm{mL}\text{ stock solution. }\\ \therefore 0.08\times 36.5\mathrm{gHCl}\text{ will be present in }\frac{0.08\times 36.5}{0.365}=8.0\mathrm{mL}\end{array}$