As we know,
Time period = 4 x (time a pendulum bob takes to move from the mean position to one end).
Given,
Time a pendulum bob takes to move from mean position to one end = 0.2s
Substituting the value in the equation above we get,
Time taken to complete one oscillation (T) = 4 × 0.2 s
= 0.8 s
Hence, time period of the pendulum = 0.8 s