You can put this solution on YOUR website! If the smaller piece is 1/13 of the larger, then the larger is 13 times as long as the smaller. So
let x = shorter piece length
then 13x = longer piece length
The lengths of the two pieces are x=13 and 13x = 169.
I didn't see the other tutor's solution before I posted mine....
But note that working the problem with fractions is a bit more difficult (a LOT more difficult for some people!); so I avoid using fractions if it is easy to do so.