Kristy asks lonnie of a number add 3 to it multiply the sum by 2 and then subtract 6. Let n stand for Lonnies number. What expression could represent Lonnies final number.

Let the number be x. Then according to the question,

Step 1 : - Adding 3

=> x + 3

Step 2 : - Multiply the sum by 2

=> 2 * (x + 3)

Step 3 : - Subtract 6

=> 2 (x + 3) - 6

Thus the expression becomes 2 (x + 3) - 6.