Cole grew 2 3/4 inches last year kelly grew the same amount which fraction below represent the number of inches that kelly grew last year

You didn't mention the fraction however, 

2 3/4 can be 11/4 as an improper fraction.

3/4 can change into anything such as, 12/16 or 3000/4000 while 2 still remains the same.
Let me know if you need any additional help. =)

the law of definite proportions states samples of a compound will always contain the same proportion of elements by mass. in other words, a given compound will always contain the same elements in the same proportions by mass.the law of multiple proportions states when two elements combine with each other to form more than one compound, then the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.