Answer:
It's irrelevant.
Explanation:
20 theater tickets cost 20T, 16 cinema tickets cost 16C.
Their sum is 20T+16C
You can factor a 4 out of this expression to get 4(5T+4C).
The two expressions are completely equivalent: there is no reason, in general, to prefer 20T+16C or 4(5T+4C).
Sometimes, the exercise may ask explicitly for the factored form.
In other cases, one of the two expression might be more useful: if you had to divide everything by 2, of course it's easier to write

If instead you had to subtract 10T, it would be more useful to write

To recap, 20T+16C and 4(5T+4C) are completely equivalent, and unless you have explicit requests, you may prefer one or the other depending on the calculations you have to do.