Answer:
Step-by-step explanation:
Write a list of all possible outcomes
1-2
1-3
1-4
2-1
2-3
2-4
3-1
3-2
3-4
4-1
4-2
4-3
There are 12 possible outcomes. How many of them have totals of 6 or 7
I count 4
So the probability is 4/12 = 1/3, just as you said.
Is there an easier way?
You might be able to get the 12 easier.
You have 4 choices for the first number and 3 for the second.
P(12) = 4*3 = 12
Getting 6 or 7 might be somewhat trickier.
4 and 3 make seven. That gives two ways 4-3 and 3-4
4 and 2 make six. That gives 2 more ways 4-2 and 2-4
That's all that's possible.
answer: 4 ways make success. The total number of ways is 12.