Question

Sarah and Nancy each drive 600 miles. Sarah's average speed is represented by x miles per hour. What does the denominator of the rational expression 600/x−4 mean in the context of this situation?

a) The denominator represents Nancy's average speed if she averages 4 mph less than Sarah.
b) The denominator represents the time required for Nancy to drive 600 mi.
c)The denominator represents Nancy's average speed if she averages 4 mph more than Sarah.
d)The denominator represents the time required for Sarah to drive 600 mi.

Answer 1

Option a - The denominator represents Nancy's average speed if she averages 4 mph less than Sarah.

Explanation:

Given : Sarah and Nancy each drive 600 miles. Sarah's average speed is represented by x miles per hour.

To find : What does the denominator of the rational expression
`(600)/(x-4)` mean in the context of this situation?

Solution :

The denominator of the rational expression
`(600)/(x-4)` is x-4.

As we know, x represent Sarah's average speed.

So, x-4 will also represent the average speed where x-4 represents 4 mph less than the average speed of Sarah, x.

Therefore, Option 'a' is correct.

The denominator represents Nancy's average speed if she averages 4 mph less than Sarah.

Answer 2

The denominator of the rational expression 600/(x-4) is x-4.

We know x represents Sarah’s average speed. So x-4 will also represents the average speed. And x-4 represents 4 mph less than the average speed of Sarah, x.

Therefore, option a) is correct.