The following are the text equivalents for each of the incorrect expressions:
$$ (3)(5)+n=(2-3)n $$
Three times five plus a number is equal to a number times the difference between 2 and 3.
$$ (3)(5)+n=3-2n $$
Three times five plus a number is equal to 3 less than 2 times a number
$$ 3(5+n) =3-2n $$
3 times the sum of five and a number is equal to 3 less than 2 times a number
It may be helpful to replace a number with an actual number and think about which order you would do first. For example, how would you calculate "3 times the sum of 5 and 1" and "3 less than 2 times 1"?
$$ 3 (5+1 ) $$
$$ 2(1)-3 $$
Replace the variable back into the expressions once the method seems reasonable.
$$ 3(5+n) $$
$$ 2(n)-3 $$
$$ \boxed{3(5+n)=2n-3} $$