Let's convert 1 3/7 to an improper fraction, and 13 to an improper fraction.
Then multiply=
10/7 x 13/1
But wait! we are dividing so we need to flip "10/7"
7/10x13/1=91/10
Now we reduce that fraction down to 9 1/10
Then we convert that to dollars and cents.
Then we find that they paid $9.10 per kilogram
