This one involves inverting the `25/13` to give `13/25` and then multiplying by that `13/25`.
`5/16 -: 25/13=5/16xx13/25`
Then we cancel the 5 on top with the 25 on bottom, to give `1/5`.
`=1/16 xx 13/5`
`=13/80`
To get the last line is simply:
1 × 13 = 13 on top; and
16 × 5 = 80 on bottom