first of all 3 7/9 is a mixed number but if you need an improper fraction then it will be 34/9 because you have to multiply 3 and 9 then add that with 7 and that's how you get 34/9. Also you always leave the denominator in the mixed fraction the same in the improper fraction. the thing i told you about 3 times 9 then add 7 is the numerator.