If you roll a number cube 40 times, about how often can you expect to roll a 2?

(1/6) * 40 = ?

To estimate how often you can expect to roll a 2 when rolling a number cube 40 times, you need to understand the concept of probability.

Here's how to calculate it step by step:

1. Determine the number of possible outcomes: A standard number cube has six sides, numbered 1 to 6. So, there are six possible outcomes when rolling the cube.

2. Identify the desired outcome: In this case, the desired outcome is rolling a 2.

3. Calculate the probability of rolling a 2 on a single roll: Since there is only one side with a 2 out of six possible outcomes, the probability of rolling a 2 on a single roll is 1/6.

4. Calculate the expected number of times rolling a 2: To estimate the expected number of times you can roll a 2, multiply the probability of rolling a 2 on a single roll by the number of rolls. So, the expected number of times rolling a 2 is (1/6) * 40 = 6.67.

5. Round the expected value to get a meaningful answer: Since you cannot roll a fractional number of times, round the expected value. In this case, rounding 6.67 to a whole number gives an expected value of 7.

Therefore, when rolling a number cube 40 times, you can expect to roll a 2 approximately 7 times.