On a 5 question multiplechoice test where each question has

On a 5 question multiple-choice test, where each question has 4 answers, what would be the probability of getting at least one question wrong? Give your answer as a fraction (or for better results, enter the actual operation into the box and check answer with \"preview\")

Solution

Probability of getting a question right is :1/4

Hence probability of getting all questions right =(1/4)^4=1/256

Hence probabiity of getting at least one question wrong is:1-1/256=255/256