Question

11 feet 8 inches plus 2 feet 9 inches

Answer 1

14 feet and 5 inches.

Answer 2

11 ft    8 in
2 ft     9 in
-----------------add
13 ft    17 in

1 ft = 12 in.....so 17 in = 1 ft 5 in

13 ft + 1 ft  5 in = 14 ft 5 in <=== 14 ft and 5 inches