Answer:
one 2
one 3
two 4's
one 5
one 6
Explanation:
We can use the combination formula to derive how many sets of two can be obtained from this set of 4 numbers. We are using the combination formula instead of the permutation formula because, in this situation, order doesn't matter; the mean of 1 and 3 is the same as the mean of 3 and 1.
where
is the number of things to choose from and
is the number of things we are choosing. Hence the equation for this problem is:
So, there are 6 ways to pick 2 cards from a total of 4. We can lay out these 6 possibilities from the given numbers on each card:
(1, 3) (3, 5) (5, 7)
(1, 5) (3, 7)
(1, 7)
Then, we can calculate the mean, or average, of each.
2 4 6
3 5
4
Finally, we can conclude that the distribution of the means for each possible set of number pairs is:
one 2
one 3
two 4's
one 5
one 6