<p>If the probability that John will buy a certain product is 3/5, that Bill will buy that product is 2/3, and that Sue will buy that product is 1/4, what is the probability that at least one of them will buy the product?</p>
<p>Since these are independent events, I thought you could simply multiply all the fractions, which gives 1/10 as the answer, but the explanation states that you must first find the probability that each individual does not buy the product. So to do that, you subtract each fraction from one, leaving you with fractions of 2/5, 1/3, and 3/4. Then you multiply them and get 1/10. To find the final answer, do 1 - 1/10 which is 9/10 (the correct answer) </p>
<p>I don't understand why you have to do all of that. I thought for independent events all you do is just multiply all the probabilities and that give you the answer. SOmeone explain!!</p>