Standard Mathematics Primary 5 Percentage

A shop offers a discount of 20% on all items. After the discount, GST of 9% is charged on the discounted price. The final price of a microwave (after discount and GST) is $392. Find the ORIGINAL price of the microwave (before discount).

A $450
B $400
C $420
D $500
Show Worked Solution

Worked Solution

Step 1: Let the original price = x. After 20% discount, price = 0.8x. Step 2: After 9% GST on the discounted price: 0.8x × 1.09 = 0.872x. Step 3: 0.872x = $392 → x = $392 ÷ 0.872 ≈ $450. Answer: $450

Correct answer: $450

Want more questions like this? Superholic Lab has 10,000+ MOE-aligned questions with full worked solutions.

Start Free Trial — 7 Days Free