the average weight of a , b and c is 60 kg . if the average weight of a and b be 70 kg and that of b and c be 50 kg , then the weight of b is :
n0 = 60.0
n1 = 70.0
n2 = 50.0
t0 = n1 * 2.0
t1 = n2 * 2.0
t2 = n0 * 3.0
t3 = t0 + t1
answer = t3 - t2
print(answer)