help me with this math problem! a probability problem

<p>The probability of having homework in math is 9/10. The probability of having homework in science is 5/6. What is the probability of having homework in neither math nor science?</p>

<p>1/60.</p>

<p>Explanation: You already only don’t have math 1 in 10 times, but you also have to not have science. That only happens 1 in 6 times, so of the times you don’t have math, only 1 in 6 don’t have science, so you have to not have math 6 times as much, so the answer is 1 in 60.</p>

<p>Math Explanation:</p>

<p>Find chances of NOT having homework: Math: 1/10 and Science: 1/6</p>

<p>1/10 x 1/6 = 1/60</p>

<p>Yeah that makes sense!! Thanks!</p>

<p>Why can’t you add 1/10 + 1/6 to get the probability of having neither?</p>

<p>Because it is 1/6th of the time you don’t have math, which is 1 in 10. 4/15(your answer) wouldn’t make sense because that would mean you don’t have both more often than you don’t have one, which isn’t possible.</p>

<p>

because 1/10 + 1/6 is the probability of either not having math, or not having science, instead of not having both.</p>

<p>math and science homework are independent events, so you multiply their probabilities in order to find out the probability that they will simultaneously happen (or not happen)</p>

<p>you add them together if they are mutually exclusive events, meaning that both cannot happen at the same time.</p>

<p>Would the SAT just ask you the probability of both things happening together and multiply and barely each things and addition?</p>

<p>^I want to help, but I have no idea what you are trying to ask</p>