If you roll two dice, what is the probability that the numbers add to 7? Why?

1/6

Step-by-step explanation:

possible combinations are = 1-6,2-5,3-4,4-3,5-2,6-1

so probability = 6 * 1/36 = 1/6

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.

Step-by-step explanation:

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