Answer:
D. 40
Step-by-step explanation:
You have 400 and you want 10%.
if you divide it by 10 you get 40.
In this equation 10% is dividing by 10.
You can even all them all up to get the original number
40+40+40+40+40+40+40+40+40+40= 400
this adding can equal 4 x 10 which is simpler.
