A town had a water storage of 12,000 liters at the beginning of the month. By the end of the month, only 10,800 liters were left. A student was asked to find the percentage decrease in water storage and gave the following solution:
Original quantity = 12,000; New quantity = 10,800
% decrease = 10,800 ÷ 12,000 × 100 = 90%
Which of the following best describes the student’s understanding?
1
The student has correctly applied the concept of percentage and arrived at the right answer.
2
The student understands the percentage formula but applied it to the wrong quantity.
3
The student made a minor calculation error but understands the concept.
4
The student has misunderstood the entire concept of percentage.