Self-documenting code

Look at the code below. You can see comments that start with "#".

# calculating a percentage of a number 

# given numbers
a = 3 
b = 15
c = 27

# the number from which the percentage is to be calculated
d = 33

pr_1 = (a/d)*100
pr_2 = (b/d)*100
pr_3 = (c/d)*100

# displaying results on the screen   
print(pr_1)
print(pr_2)
print(pr_3)

There are numerous repetitive actions in this code. How can you shorten it without skipping the necessary steps?