Answer
$ 9 $ astronomical units farther from the sun is Uranus than Earth.
Work Step by Step
The given formula is
$ d=\frac{3(2^{n-2})+4}{10} $
Where, $ d $ is measured in astronomical units and $ n $ is the number of planet from the sun.
For earth substitute $ n=3 $ into the formula.
$ d=\frac{3(2^{3-2})+4}{10} $
$ d=\frac{3(2^{1})+4}{10} $
$ d=\frac{3 \cdot 2+4}{10} $
$ d=\frac{ 6+4}{10} $
$ d=\frac{ 10}{10} $
$ d=1 $
For Uranus substitute $ n=7 $ into the formula.
$ d=\frac{3(2^{7-2})+4}{10} $
$ d=\frac{3(2^{5})+4}{10} $
$ d=\frac{3 \cdot 32+4}{10} $
$ d=\frac{ 96+4}{10} $
$ d=\frac{ 100}{10} $
$ d=10 $
The difference between both distances from sun.
$ 10 - 1 = 9 $.
