Use a straightedge to divide the fraction bar into 6 equal parts then shade 4 parts

J= r + 9 because since jessica rode 9 more miles than roger, you add 9 miles to rogers mileage.

If i think this is what your asking, he should look at the grams or pounds/ounces and compare the to their cost then max can identify which one is proportional and which is not ( i think xd)