# What is the expected value of the sum of the numbers shown in rolling a dice twice?

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The expectation of the sum of two (independent) dice is the sum of expectations of each die, which is 3.5 + 3.5 = 7. Similarly, for N dice throws, the expectation of the sum should be N * 3.5. If you’re taking only the maximum value of the two dice throws, then your answer 4.47 is correct.

## What is the expected value of a roll of a dice?

When you roll a fair die you have an equal chance of getting each of the six numbers 1 to 6. The expected value of your die roll, however, is 3.5.

## What is the expected sum of the numbers on the dice?

The expected value of the random variable is (in some sense) its average value. You compute it by multiplying each value x of the random variable by the probability P(X=x), and then adding up the results. So the average sum of dice is: E(X) = 2 . 1/36 + 3 . 2/36 + ….

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## When rolling two dice What is the probability of rolling a sum of 7?

For each of the possible outcomes add the numbers on the two dice and count how many times this sum is 7. If you do so you will find that the sum is 7 for 6 of the possible outcomes. Thus the sum is a 7 in 6 of the 36 outcomes and hence the probability of rolling a 7 is 6/36 = 1/6.

## What is the probability of getting a sum of 9 when a dice is rolled twice?

→ Required Probability = (total Possible outcomes of sum is 9 or 11) / (total Possible outcomes) = (4/36) = (1/9) (Ans.) what is the mean deviation of the data:8,9,12,15,16,20,24,30,32,34?

## What is the expected value of the sum of three dice?

Rolling three dice would give you an expected outcome of 10.5. (It may be interesting to note that the expected value is an impossible occurrence, since dice have a whole number of dots.

## How do you find the expected value?

1.To find the expected value, use the formula: E(x) = x1 * P(x1) + x2 * P(x2) + … + xn * P(xn) .

How to find the expected value?

1. Multiply each random value by its probability of occurring.
2. Sum all the products from Step 1.
3. The result is the expected value.

## How do you find the expected value of a dice game?

To calculate the expected value, we multiply the value times it probability and sum the results. So the expected value of this game is: (100 * 1/216) + (-1 * 215/216) = -115/216 = -53 cents, approximately. So you can expect to lose about 53 cents on average for every roll of the dice!

## What is the expectation of getting 5 on a roll of a dice?

Two (6-sided) dice roll probability table

Roll a… Probability
4 6/36 (16.667%)
5 10/36 (27.778%)
6 15/36 (41.667%)
7 21/36 (58.333%)

## What is the probability of sum of two dice?

If the two dice are fair and independent , each possibility (a,b) is equally likely. Because there are 36 possibilities in all, and the sum of their probabilities must equal 1, each singleton event {(a,b)} is assigned probability equal to 1/36.

## What is the probability of a sum of 7 or 11?

What is the probability that the sum will be a 7 or 11? There are 36 possible outcomes for the two dice. So, the probability is 8/36 = 2/9.

## When two dice are rolled find the probability of getting a sum of 6 or 7?

Hence probability of getting a sum of 6 or 7 is 1136 .

## What is the probability of getting sum of 9?

So, P(sum of 9) = 1/9.

## What is the probability of getting a total of nine?

Therefore, the probability of rolling a 9 with two dice is 14 .

## What is the probability that the numbers add up to 9?

There are 36 possible outcomes. Of those, the ones that total 9 are 3-6, 6-3, 4-5, or 5-4. That makes 4 out of 36. So the probability of getting a total of 9 by throwing 2 dice is 4/36 or 1/9.