UPCAT Mathematics practice question 4: A shirt sells for ₱480 after a 20% discount. What was its original price?
Correct answer
D. ₱600
The sale price is 80% of the original, so the original is 480 ÷ 0.80 = 600. Adding 20% to 480 gives 576, which is the common trap.
The question
A shirt sells for ₱480 after a 20% discount. What was its original price?
- Option A: ₱500
- Option B: ₱576
- Option C: ₱640
- Option D: ₱600Correct
Why D is correct
The sale price is 80% of the original, so the original is 480 ÷ 0.80 = 600. Adding 20% to 480 gives 576, which is the common trap.
Why the other options are wrong
- A ₱500
- Comes from treating the ₱480 as if the discount were a flat ₱20 rather than 20 per cent.
- B ₱576
- The classic trap: adding 20% back onto 480. The discount was taken from the larger original, so adding it to the smaller sale price cannot undo it.
- C ₱640
- Divides by 0.75 instead of 0.80, i.e. treats it as a 25% discount.