Answer:
The commutative, associative, and distributive properties help you rewrite a complicated algebraic expression into one that is easier to deal with. When you rewrite an expression by a commutative property, you change the order of the numbers being added or multiplied.
Step-by-step explanation:
<h2>
Hello!</h2>
The answer is:
First employee: 3 gallons
Second employee: 3 1/3 gallons
Total: 
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Why?</h2>
From the statement we know:
First employee uses 3/4 gallon each our, for 4 hours the will use:

Second employee uses 1 2/3 (5/3) gallon every 2 hours, meaning 5/6 gallon each hour.

Remember, to sum (algebraic sum) fractions we should follow the next steps:
First: Multiply both fractions denominators by each other in order to get the denominator of the new fraction.
Second: Multiply the numerator of the first fraction by the denominator of the second fraction.
Third: Multiply the denominator of the first fraction by the denominator of the second fraction.
Fourth: Sum (algebraic sum) each result and divide it into the number obtained from the first step (denominator of the new fraction).
Example:

Have a nice day!
Answer:

Step-by-step explanation:
Given this function:

We need to find the value of:

This is really simple because the problem give us the following data:

Using this data we can write a 2x2 system of equations like this:
Let:

and

Our system will be:

We can solve this system using different methods, however I will use elimination method because I believe it is really simple. So:

Replacing
into (1)

Now we found the values of
and
, our function is given by:

Let's verify it:


As you can see the function satisfies the data provided by the problem. So we can conclude that it is correct.
Finally, let's find
for
:

Hence:

Answer:
7. 1/10 or 10%
9.5/10
11.5/10
13.9/10
Step-by-step explanation: