Let the rational number be x/y
According to the question we can write as y=x+7
Which implies x=y-7 and (x+17)/(y-6) = 2
Now substituting the value of x in above equation we get
(y-7+17)/(y-6) = 2
Now by rearranging,
(y-7+17)=2(y-6)
y+10=2y-12
y=22
But x=y-7=22-7=15
So the number is 15/22