the statement 3 times the difference of n ans 5 is written as 3 ( n - 5) , the difference (n -5) is multiplied by 3.
when we say 16 more than thw double number n. It means that we add 16 to double n (which is 2n) , that is, 16 + 2n
so 3 times the difference of a number "n" and five is sixteen more than double the number "n" is simply 3(n -5) = 16 + 2n