Leaving Certificate Mathematics Question 12 by Maths Grinds

A student believes that toast is more likely to land buttered side down when it falls to the ground. He conducts an experiment in which he drops buttered toast onto the floor. He observes that, out of 128 drops, the toast landed buttered side down 70 times.

Calculate the relative frequency. Is this relative frequency a good estimate of the probability? Why or why not?