Question

To the nearest thousand what was E (X) expected number of bases for Alex Rodriguez in a typical at bat in 2007

Answer 1

Given the following table that arranges the data of Alex Rodriguez hits in his 2007 MVP season for the New York Yankees,  in terms of the number of bases for a hit, counting 0 bases for the times when he did not get a hit and 4 bases for home runs.

Number of Bases (x):    0   1    2  3  4
Number of Times f(x): 400 98 31 0 54

Recall that the expected value of an event is given by the sum of the products of x and f(x).

Thus, E(x) = ∑xf(x) = 0(400) + 1(98) + 2(31) + 3(0) + 4(54) = 98 + 62 + 216 = 376.

Given that he made a total of 583 at bats, E(x) can be expressed as 376 / 583 = 0.645 to the nearest thousandth.

Therefore, E(X), the expected number of bases for Alex Rodriguez in a typical at bat in 2007 is 0.645