What is the problem with my code? Can someone help?

Question

Code
houses = int(input())

chance = round(2/houses*100)

while houses>=3:
print(chance)
break
#your code goes here

Question
You go trick or treating with a friend and all but three of the houses that you visit are giving out candy. One house that you visit is giving out toothbrushes and two houses are giving out dollar bills.

Task
Given the input of the total number of houses that you visited, what is the percentage chance that one random item pulled from your bag is a dollar bill?

Input Format
An integer (>=3) representing the total number of houses that you visited.

Output Format
A percentage value rounded up to the nearest whole number.

Sample Input
4

Sample Output
50

Answer 1

This is the part you missed: A percentage value rounded up to the nearest whole number.

Python's round function doesn't always round up. round(3.2) is 3.0.

The following should work with minimal changes to your code:
import math
houses = int(input())

chance = math.ceil(2/houses*100)

while houses>=3:
print(chance)
break

The while-loop that breaks after only 1 pass looks a bit silly and there isn't much need for the choices variable, though. The following is a simplified version:
import math
houses = int(input())
print(math.ceil(2/houses*100))