Given, 

Primary voltage V1 = 220 V 

Primary turns N1 = 200 turns 

Secondary turns N2 = ? 

Secondary voltage V2 = 33 V 

According to formula, 

\(\frac{V2}{V1}=\frac{N2}{N1}\)

N2 = 200 * 33 / 220 

N2 = 30 

Hence, the number of turns in secondary coil must be 30 turns.