Bella rolls 2 number cubes 60 times. How many times can she expect the sum of the numbers to be 10 or greater?

To find the number of times Bella can expect the sum of the numbers to be 10 or greater, we need to calculate the probability of getting a sum of 10 or greater on a single roll and then multiply it by the number of rolls.

First, let's determine the probability of getting a sum of 10 or greater on a single roll of two number cubes.

A number cube has 6 sides numbered from 1 to 6, so there are a total of 6*6 = 36 possible outcomes when rolling two number cubes.

Next, let's count the number of outcomes that result in a sum of 10 or greater. To simplify this, we can construct a chart of all possible outcomes:

| Cube 1 | Cube 2 | Sum |
|---------|---------|-----|
| 1 | 1 | 2 |
| 1 | 2 | 3 |
| 1 | 3 | 4 |
| 1 | 4 | 5 |
| 1 | 5 | 6 |
| 1 | 6 | 7 |
| 2 | 1 | 3 |
| 2 | 2 | 4 |
| 2 | 3 | 5 |
| 2 | 4 | 6 |
| 2 | 5 | 7 |
| 2 | 6 | 8 |
| 3 | 1 | 4 |
| 3 | 2 | 5 |
| 3 | 3 | 6 |
| 3 | 4 | 7 |
| 3 | 5 | 8 |
| 3 | 6 | 9 |
| 4 | 1 | 5 |
| 4 | 2 | 6 |
| 4 | 3 | 7 |
| 4 | 4 | 8 |
| 4 | 5 | 9 |
| 4 | 6 | 10 |
| 5 | 1 | 6 |
| 5 | 2 | 7 |
| 5 | 3 | 8 |
| 5 | 4 | 9 |
| 5 | 5 | 10 |
| 5 | 6 | 11 |
| 6 | 1 | 7 |
| 6 | 2 | 8 |
| 6 | 3 | 9 |
| 6 | 4 | 10 |
| 6 | 5 | 11 |
| 6 | 6 | 12 |

Out of the 36 possible outcomes, there are 27 outcomes that result in a sum of 10 or greater.

Now, let's calculate the probability of getting a sum of 10 or greater on a single roll:
Probability = Number of favorable outcomes / Total number of possible outcomes
Probability = 27 / 36
Probability = 3 / 4

Therefore, the probability of getting a sum of 10 or greater on a single roll is 3/4.

To find how many times Bella can expect the sum of the numbers to be 10 or greater in 60 rolls, we multiply the probability by the number of rolls:
Expected number of times = Probability * Number of rolls
Expected number of times = (3/4) * 60
Expected number of times = 45

Therefore, Bella can expect the sum of the numbers to be 10 or greater around 45 times.

Out of 36 possible outcomes, the only ways to get 10 or more are

4,6 or 5,5 or 6,4
5,6 or 6,5
6,6
So, 6/36 = 1/6 is the chance of success.
1/6 of 60 is 10