#Variable declaration
N1=5.0 #no of molecules#
N2=10.0
N3=20.0
N4=20.0
N5=10.0
M1=5000.0 #molecular mass of each molecule#
M2=6000.0
M3=10000.0
M4=15000.0
M5=25000.0
#Calculation
M=(M1*N1+M2*N2+M3*N3+M4*N4+M5*N5)/(N1+N2+N3+N4+N5) #formula for number average molecular mass#
Mw=(N1*M1**2+N2*M2**2+N3*M3**2+N4*M4**2+N5*M5**2)/(M1*N1+M2*N2+M3*N3+M4*N4+M5*N5) #formula of weight-average molecular mass#
#Result
print"The number average molecular mass is %.2e"%M
print"\nThe weight average molecular mass is %.2e"%Mw