Answer:
1,816,214,400 batting orders are possible.
Step-by-step explanation:
The order is important.
Suppose we had a two player batting order.
A batting order of Jonathan Schoop and Manny Machado is a different order than Manny Machado and Jonathan Schoop. So we use the permutations formula.
Permutations formula:
The number of possible permutations of x elements from a set of n elements is given by the following formula:

A baseball coach is creating a nine-player batting order by selecting from a team of 15 players. How many different batting orders are possible?
Selection of 9 players from a set of 15 players. So

1,816,214,400 batting orders are possible.
If you are having trouble with ratios, turn them into fractions.
ex; 3 : 5 = 3/5, 8 : 10 = 8/10, 6 : 15 = 6/15
After you have turned all of your ratios into fractions, you can find a common denominator for all the fractions.
ex; 3/5, 8/10, 6/15 ⇒ 3/5, 4/5, 2/5
Now it you can easily order the ratios from least to greatest.
ex; 6 : 15, 3 : 5, 8 : 10
The answer is:
v ≈ 1272.35 in^3
Sorry if this does not help.