The reaction happening in solution is the following:
$ZnO(aq)+2HCl(aq)->ZnCl_2(aq)+H_2O(l)$
Since the hydrochloric acid ($HCl$) is in excess, therefore, the number of moles of Zinc oxide ($ZnO$) will determine the mass of Zinc chloride ($ZnCl$).
Using dimensional analysis, we find:
$?g ZnCl_2=3.6cancel("mol " ZnO)xx(1 cancel ("mol "ZnCl_2))/(1cancel("mol " ZnO))xx(136.3"g "ZnCl_2)/(1 cancel ("mol "ZnCl_2))=490.7"g "ZnCl_2$