Octal Numbers

This is a variation on a Linux challenge I found elsewhere on the Internet. I created a file of numbers as follows:
 
Red Hat >cat file_of_numbers
134

065

258

168

Red Hat >
 
I wrote the following simple script to add the numbers, hoping that the result would be 625:
 
Red Hat >cat count_total.bash

#!/bin/bash

total=0

for x in `cat file_of_numbers`

do

((total+=$x))

done

echo "Total = $total"

Red Hat >
 
However, when I ran it the result was slightly different:
 
Red Hat >./count_total.bash

Total = 613

Red Hat >
 
That was because the leading zero in 065 told Linux to treat it as octal which equals 6x8+5 = 53 in decimal.
 
I removed the leading zero:
 
Red Hat >cat file_of_numbers

134

65

258

168

Red Hat >
 
…then Linux gave me the answer I wanted:
 
Red Hat >./count_total.bash

Total = 625

Red Hat >