7 1/2=r-5 2/3. R=13 1/6. I got my answer by doing the inverse operation of subtracting 5 2/3 I added 5 2/3 to 5 2/3 I got 0 leaving N alone. I also added 5 2/3 to 7 1/2 I had to find the least common denominator and I got 6 I made 5 2/3 into 5 4/6 since they are equavelent fractions. I made 7 1/2 into 7 3/6 since they are equivalent and I added both fractions and got 12 7/6 and I made 13 1/6.