Answer:
The square of the orbital periods of the planets are directly proportional to the cubes of their average distances from the Sun
Explanation:
Kepler's third law of planetary motion can be summarized as follows:
"The square of the orbital periods of the planets are directly proportional to the cubes of their average distances from the Sun"
In formula, this is written as follows:

where:
r is the average distance of the planet from the Sun
G is the gravitational constant
M is the mass of the Sun
T is the orbital period of the planet
From the formula, we see that the factor
is constant for every planet. So, if we call this constant factor k, the equation can be rewritten as

which means that the cube of the mean distance of the planet from the Sun (r) is directly proportional to the square of the orbital period (T).