Two dice are rolled. What is the probability [tex]\( P(\text{sum is 3}) \)[/tex]? Express your answer as a decimal (rounded to 4 places) or a reduced fraction.



Answer :

Absolutely, let's solve this step-by-step.

First, let's determine the total number of possible outcomes when rolling two dice:

1. Calculating Total Number of Possible Outcomes:
- Each die has 6 faces.
- Therefore, the total number of possible outcomes when rolling two dice is:
[tex]\[ 6 \times 6 = 36 \][/tex]

Now, let's identify the number of favorable outcomes where the sum of the numbers on the two dice equals 3:

2. Identifying Favorable Outcomes:
- We list all possible combinations of rolling two dice where the sum is 3:
- (1, 2)
- (2, 1)
- So, there are 2 favorable outcomes.

3. Calculating the Probability:
- The probability [tex]\( P \)[/tex] of an event happening is given by the ratio of the number of favorable outcomes to the total number of possible outcomes.
- Therefore, the probability [tex]\( P \)[/tex] that the sum of the numbers on two dice is 3 is:
[tex]\[ P(\text{sum is 3}) = \frac{\text{Number of favorable outcomes}}{\text{Total number of possible outcomes}} = \frac{2}{36} \][/tex]
- Simplifying this fraction, we get:
[tex]\[ P(\text{sum is 3}) = \frac{1}{18} \][/tex]

4. Expressing the Probability as a Decimal:
- To express this probability as a decimal, we divide:
[tex]\[ \frac{1}{18} \approx 0.05555555555555555 \][/tex]
- Rounding this to 4 decimal places:
[tex]\[ 0.0556 \][/tex]

So, the probability [tex]\( P \)[/tex] that the sum of the numbers on two dice is 3, expressed as a decimal rounded to 4 places, is:

[tex]\[ P(\text{sum is 3}) \approx 0.0556 \][/tex]

Hence, the final result is:
- Total number of possible outcomes: 36
- Number of favorable outcomes: 2
- Probability that the sum is 3: [tex]\( \approx 0.0556 \)[/tex]