first, convert the mixed numbers to improper fractions:
15 1/2=31/2
4 1/4=17/4
now, we have to find the ratio of 31/2 to 17/4
multiply both by 4 to get rid of the denominator (this won't change the ratio because we're multiplying both by 4)
so the ratio is 62 to 17=62/17=3 11/17
