a certain list consists of 21 different numbers . if n is in the list and n is 5 times the average ( arithmetic mean ) of the other 20 numbers in the list , then n is what fraction of the sum of the 21 numbers in the list ?
n0 = 21.0
n1 = 5.0
n2 = 20.0
n3 = 21.0
t0 = n2 / 4.0
t1 = 1.0 * 1.0
t2 = n0 + t0
t3 = t2 / 4.0
t4 = t3 * 2.0
t5 = t4 - n1
t6 = t5 - 3.0
answer = t1 / t6
print(answer)