import sys

for x in sys.stdin:

    s=a=float(x)

    for i in range(9):

        if i%2==0: a*=2

        else: a/=3

        s+=a

    print(s)
import sys

for x in sys.stdin:

    a=float(x)

    s=a

    for i in range(9):

        if i%2: a/=3

        else: a*=2

        s+=a

    print(s)
import sys

for x in sys.stdin:
    s = a = float(x)
    for i in range(9):
        if i % 2 == 0:
            a *= 2
        else:
            a /= 3
        s += a
    print(s)

import sys

for x in sys.stdin:
    a = float(x)
    s = a
    for i in range(9):
        if i % 2:
            a /= 3
        else:
            a *= 2
        s += a
    print(s)

-    s = a = float(x) +    a = float(x) +    s = a -        if i % 2 == 0: +        if i % 2: +            a /= 3 +        else: -        else: -            a /= 3