Evelyn rolled two 1-6 cubes 72 times. How many times should she predict she will roll a sum of 5?
12
You can predict that Evelyn will roll a sum of 5 about 12 times.
To determine the number of times Evelyn can expect to roll a sum of 5 when rolling two 1-6 cubes, we need to calculate the probability of rolling a sum of 5 and multiply it by the total number of rolls.
First, let's calculate the probability of rolling a sum of 5 with two cubes. There are a total of 36 possible outcomes when rolling two 1-6 cubes (6 outcomes for the first cube multiplied by 6 outcomes for the second cube). Out of these 36 outcomes, there are 4 outcomes that result in a sum of 5: (1, 4), (2, 3), (3, 2), and (4, 1).
So, the probability of rolling a sum of 5 is 4/36, which simplifies to 1/9.
Now, we can calculate how many times Evelyn can expect to roll a sum of 5 by multiplying the probability by the total number of rolls:
Expected number of rolls = Probability of rolling a sum of 5 × Total number of rolls
Expected number of rolls = (1/9) × 72
Expected number of rolls = 8
Therefore, Evelyn should predict that she is likely to roll a sum of 5 around 8 times when rolling two 1-6 cubes 72 times.
To determine the number of times Evelyn should predict she will roll a sum of 5 when rolling two 1-6 cubes 72 times, we can use probability.
First, let's analyze the possible outcomes when rolling two 1-6 cubes. Each cube has 6 faces numbered from 1 to 6, so there are 6 possible outcomes for each cube. Since we are rolling two cubes, the total number of possible outcomes is 6 x 6 = 36.
Next, let's determine the number of outcomes that result in a sum of 5. We can create a table to visualize the outcomes:
Cube 1 | Cube 2 | Sum
-------|--------|-----
1 | 4 | 5
2 | 3 | 5
3 | 2 | 5
4 | 1 | 5
From the table, we can see that there are 4 outcomes that result in a sum of 5.
Now, let's calculate the probability of rolling a sum of 5. Probability is calculated by dividing the number of desired outcomes by the total number of possible outcomes. In this case, the probability is 4/36.
To predict how many times Evelyn will roll a sum of 5 in 72 rolls, we can multiply the probability of rolling a 5 by the number of rolls. So, the prediction is (4/36) x 72 = 8.
Therefore, Evelyn should predict that she will roll a sum of 5 around 8 times when rolling two 1-6 cubes 72 times.