from fractions import Fraction

X = ['w']*5 + ['b']*4
Y = ['w']*7 + ['b']*6
count=0
visited=0

for i in X:
    tem=Y+[i]
    #print(tem)
    for j in tem:
        if j=="b":
            count+=1
        visited+=1
        
print(Fraction(count,visited))