rprogn, 166 bytes

Result

WA

Duration

482ms

Code [DL]

read "v1" =
read "v2" =
read "v3" =
read "v4" =

v1 0 index v1 1 index 10 * + "x3" =
v1 3 index v1 4 index 10 * + "x2" =
v1 6 index v1 7 index 10 * + "x1" =

x1 x2 x3

stdin

13 16 68
76 05 07
03 84 19
90 41 83

stdout

18.0
 10.0
 60.0

stderr

strace