Ecperts plz tell me.. What is formula to find number of turns in a transformer... Plz tell fast i hv only 2 hrs in my exam.... Plzzzz urgent

Dear Student ,
The formula to find the number of turns in a transformer :
$\frac{E_s}{E_p}=\frac{N_s}{N_p}$
Where E_s and E_p are the voltage of the secondary and primary coils and N_s & N_p are the number of turns of the secondary and primary coil .
Regards