Two friends were each rolling a die. After they rolled, they found the sum of the numbers showing on each die. What is the probability that the sum is 7?
I added the sides together and simplified to get 1/6, but I don't think that's right.
The prob that you get a 7 when rolling two dice = 1/6
so when two friends roll , (the same result as you rolling twice)
prob(2 7's ) = (1/6)(1/6) = 1/36
thanks!
To find the probability that the sum of the numbers showing on the two dice is 7, you need to calculate the number of favorable outcomes (sums that add up to 7) and divide it by the total number of possible outcomes.
The possible outcomes when rolling two dice can be determined by multiplying the number of outcomes for each die. Since each die has 6 sides, the total number of outcomes when rolling two dice is 6 * 6 = 36.
To determine the number of favorable outcomes (sums that add up to 7), you can make a list of all possible combinations and count how many of them yield a sum of 7. Here are the combinations that result in a sum of 7:
1 + 6
2 + 5
3 + 4
4 + 3
5 + 2
6 + 1
So, there are 6 favorable outcomes.
To calculate the probability, divide the number of favorable outcomes by the total number of possible outcomes:
Probability = Favorable Outcomes / Total Outcomes
= 6 / 36
= 1 / 6
Therefore, your initial calculation of 1/6 is indeed correct. The probability that the sum is 7 when rolling two dice is 1/6.