Answer:
The chance of an average six-sided number cube landing one one number is 1/6, or approximately 16.67%. When rolling a number cube 100 times, the average number of times it lands on any specific number should be fairly close to 16.67.
A 6 being rolled 42 times and 33 times means that it is very likely not to be a standard number cube. Although we cannot know for certain, the chance of this happening is very low.