a cement mixture is composed of 3 elements . by weight , 1 / 2 of the mixture is sand , 1 / 5 of the mixture is water , and the remaining 15 pounds of the mixture is gravel . what is the weight of the entire mixture in pounds ?
n0 = 3.0
n1 = 1.0
n2 = 2.0
n3 = 1.0
n4 = 5.0
n5 = 15.0
t0 = n1 / n2
t1 = n3 / n4
t2 = t0 + t1
t3 = n1 - t2
answer = n5 / t3
print(answer)