# Created by Donyo Ganchev, Agricultural University, town of Plovdiv, Bulgaria
#donyo@abv.bg
choice=None
def Concentration():
per_act_sub=input('Enter the percent of active substance in formulation : ')
per_con_ws=input('Enter the percent concentration of the pesticide solution: ')
am_ws=input('Enter the amount of pesticide solution: ')
m_val=(float(am_ws)/(((per_act_sub-per_con_ws)/10)+(per_con_ws/10)))
am_pest_ws=(per_con_ws/10)*m_val
am_water=(((per_act_sub-per_con_ws)/10)+(per_con_ws/10))*(am_ws)/(((per_act_sub-per_con_ws)/10)+(per_con_ws/10))-am_pest_ws
print \
"""
"""
print "Amount of pesticide formulation (ml or g): ", am_pest_ws
print "Amount of water in pesticide solution (ml): ", am_water
while choice!="0":
print \
"""
Pesticide Solution Concentration Program
1 - Begin calculation
0 - Exit
"""
choice= raw_input("Choice: ")
if choice == "0":
exit()
elif choice=="1":
Concentration()
