Choose a number that will produce an irrational answer when added to 7/8. PLEASE HELP ITS DUE AT MIDNIGHT.

Answer:
√7
Step-by-step explanation:
2/5, 0.404040 and 0.286 are all rational as they all can be expressed in fraction form (0.4040 can be expressed as 40/99 and 0.286 as 286/1000 (can simplify but I didn't)) sqrt7 is the only irrational number.