I am reviewing for an exam today, and, I was given a review sheet. However, I do not see how the answer is what is listed. Here is the question.
Two distinct even numbers are selected at random from the first ten even numbers greater than zero. What is the probability that the sum is 30?
I don't know, maybe he miss worded it, but as is I'm going to assume the sample space contains 10 numbers....2,4,6,8,10,12,14,16,18,20
Which, would leave me with combinations, 10,20 14,16 and 12,18. However, more if I include their reverse 20,10 16,14 and 18,12, but I am assuming again. Well, the first way I get 3/10 for an answer.What am I doing wrong? It shows an answer of 1/15 on the review sheet.The teacher could be wrong, I already found a couple wrong and I am sure of it. This problem could also have a sample space of 20 the way he worded it...I still have about 8 hours before my final...