That's easy you just need to listen in school to answer it
The denominator of the second fraction can be factored as (a-2)(2a-7), then it becomes doable. You cancel the (2a-7) factors, and are left with:

Do note that you have erased the fact that a≠0 and a≠7/2, so you should always mention that.
Answer:
If I'm not mistaken that is the answer
Answer:
18
Step-by-step explanation:
The absolute value means how far it is from 0 and 18 it 18 numbers from 0! For negative numbers its the same |-18| would be 18 as well because it is 18 numbers from 0.
Step 1. Type it into a Google search box or calculator. (You need to use a calculator anyway.) The result is
3177 4/9.
If you're doing this according to the Order of Operations, you do the multiplication and division left to right. This means the first calculation you do is
255/6 = 42.5
Next, you multiply by 672
42.5*672 = 28560
Then divide by 9
28560/9 = 3173 3/9
You continue by doing the division
37/9 = 4 1/9
And finish by adding the two results
3173 3/9 + 4 1/9 =
3174 4/9_____
If you're doing this by hand, you can recognize the first term as the product of two fractions, so is the product of numerators divided by the product of denominators.
(255*672)/(6*9)
Using your knowledge of divisibility rules, you can do the division 672/6 to simplify this to
(255*112)/9
Now, the first term and the second term have the same denominator, so you can add the numerators before you do the division.
(255*112 + 37)/9 = (28560 + 37)/9 = 28597/9
You end up having to do only two simple divisions, rather than 3 of them.
28597/9 = 3177 4/9