Find the probability of the following event:
tossing a coin heads up or rolling a 3 with a number cube.
I got: 1/2+1/6 = 2/3 but the right answer is 7/12. I don't understand how to get 7/12. Please help.
1/2 + 1/6 = 6/12 + 2/12 = 8/12 = 2/3
Neither do I. Probably a typo in the answer key.
To find the probability of the event, we need to determine the probability of tossing a coin heads up and rolling a 3 with a number cube separately, and then add the probabilities together.
Let's start with the coin toss. When tossing a fair coin, there are two possible outcomes: heads or tails. Since we are interested in heads, there is a 1/2 probability of getting heads.
Next, let's consider rolling a number cube (also known as a standard six-sided die) and getting a 3. With a number cube, there are six equally likely outcomes: 1, 2, 3, 4, 5, or 6. Since we are interested in rolling a 3, there is a 1/6 probability of getting a 3.
To find the probability of either event happening, we add the probabilities together: 1/2 + 1/6 = 4/12 + 2/12 = 6/12.
However, we can simplify the fraction by dividing both the numerator and denominator by their greatest common divisor, which is 6 in this case. Simplifying 6/12 gives us 1/2.
Therefore, the correct probability should indeed be 1/2, not 7/12 as you mentioned. It seems there might be an error in the given solution.