Answer: C. End of third day
Step-by-step explanation:
The question is asking when there will be 36 pieces left, so you start with the equation:
-6d + 54 = 36
Then, solve this equation:
-6d + 54 = 36
-6d = -18 (subtract 54 from both sides)
d = 3 (divide both sides by -6)
It will take 3 days until there are 36 pieces left, which is the end of the third day.