Any time you need to change a word problem involving a variable and you are not sure how to do it, ask yourself how would I tackle this problem with a known number and then trace what operation was used.
If I asked you what is the result if the number 7 is increased by 4, you would likely say 11. Tracing your work, you realize that you added 7 + 4 = 11.
Thus a number (e.g. n) increased by 4 is simply:
n + 4
