Answer:
3/7
Step-by-step explanation:
Lets assume the unknown number is x. x+4 5/7=12x
to get all your variables on one side, subtract x.
4 5/7=11n
Since mixed numbers are useless here, convert it to a improper fraction. 33/7=11x
Then, divide both sides by 11.
33/7÷11=3/7
11x÷11=x
x=3/7