A bunch of animals are in a room.
The probability of choosing a cat is 0.35.
The probability of choosing an animal that is grumpy is 0.2.
The probability of an animal being a cat or grumpy is 0.4.
What is the probability of choosing an animal that is not a grumpy cat?
They cover a range of subjects (ones that are often the most difficult for students and therefore require a lot of explanation) and the format is great - exactly the way studying should work! Explanation, practice, then taking a full exam. It provides a great guide for studying and the explanations are very thorough. As advertised, the best way to study when you've procrastinated and need to learn it all for the exam (and it does all the stats of what's most common for you)! – A.I, Seaquam Secondary School, Canada