Can you calculate molality from molarity if you don't know the density of the solution?

1 mol of CaCl2 weighs 111 g

if 0.2 molar is in 1 L of solution, then n will be 0.2 mol

0.2 mol weighs 0.2x111= 22.2 g

so the molality is 0.2/22.2E-3 = 1000/111

Technically you can't. However, in this case, you have only 1 significant figure (0.2M), so you probably could guess that the density of the (dilute) solution is close to the density of the pure solvent. (Alternately, the person who wrote the question may have accidentally written 0.2M when 0.2m was meant.)