They are falling under the sole influence of gravity all objects<span> will </span>fall<span> with the </span>same<span> rate of </span><span>acceleration needless of there size</span>
Since inertia is directly proportional to the mass of an object, the higher the mass the higher the inertia. In this case, 6 Kg is 100 times heavier than 0.06 Kg to imply The bowling ball has 100 times more inertia than the tennis ball because it has 100 times more mass