ANSWER

EXPLANATION
The given rational function is

We need to rationalize the denominator by multiplying both the numerator and the denominator by the conjugate of

which is

When we rationalize we obtain:

The denominator is now a difference of two squares:

We apply this property to get


This simplifies to

Or

<span>An upper quartile is the range of numbers above the median in a set. Thus, the numbers have to be rearranged mentally or on paper. Fortunately, there are an odd set of numbers, so one number, 25, is the median. The upper quartile is 30, 35, 40, 45.</span>

That's 7.68% = 7.7% (rounded)
Note: C(5, 4) is the number of combinations of 5 things taken 4 at a time. You may have seen this written as

In general,
All of the answer choices except B would be correct for this problem.