While my program gives the correct answer for these specific numbers when I run it through our system checker it comes back as 3/4 correct.. the problem being
organisms 7, growth rate 7, growth period 7, total hours 7

ORIGINAL QUESTION:
start with a population of 500 organisms, a growth rate of 2, and a growth period to achieve this rate of 6 hours. Assuming that none of the organisms die, this would imply that this population would double in size every 6 hours. Thus, after allowing 6 hours for growth, we would have 1000 organisms, and after 12 hours, we would have 2000 organisms.

Write a program that takes these inputs and displays a prediction of the total population.

MY PROGRAM:
organisms=int(input("Enter the initial number of organisms:"))
growth=float(input("Enter the rate of growth [a real number > 1]:"))
numHours=int(input("Enter the number of hours to achieve the rate of growth:"))
totalHours=int(input("Enter the total hours of growth:"))
population = organisms
hours=1
while numHours < totalHours:
population *= growth
hours += numHours
if hours >= totalHours:
break
print(" The total population is ", population)