Answer:
7 ft 9 inches
Explanation:
3 ft 9 in + 4 ft = 7 ft 9 inches
All you have to do is add the feet with the feet and add the inches with the inches. They want you to add 3 ft + 4 ft, which is 7 ft. There are no inches to add to 9 in, so that just remains 9 in.
Therefore, your answer is 7 ft 9 in.
I hope this helps! Have a lovely day!! :)