Homer wants to read 2 books from his collection. He has 6 adventure books and 4 horror books. He chooses 2 books randomly and simultaneously. What is the probability that he chose 1 adventure book and 1 horror book?	Choices
A) 16/25 B) 24/45 C) 7/8 D) 12/105 E) 10/24
The probability is equal to the number of desired choices divided by the total number of possibilities.   Probability = Favorable/Total   Total = 10C2 = 10*9/2= 
<gadget id="calculator">10*9/2</gadget>
<output>45</output>
45   Favorable:   Pick 1 adventure book out of 6 adventure books   AND   Pick horror book out of 4 horror books   6C1*4C1= 6*4= 
<gadget id="calculator">6*4</gadget>
<output>24</output>
24   P=24/45   When you use combination method, it is picking all possible cases and the order doesn't matter. Whereas, upon choosing probability method to solve, order matters.   Thus,   Total Probability:   Probability of choosing an adventure book first AND Probability of choosing a horror book   OR   Probability of choosing a horror book first AND Probability of choosing an adventure book   Answer: 24/45
<result>B</result>
Homer wants to read 2 books from his collection. He has 6 adventure books and 4 horror books. He chooses 2 books randomly and simultaneously. What is the probability that he chose 1 adventure book and 1 horror book?