Abi bought one television set at 20% discount off its original price. She paid a total of $436 for it, which was inclusive of 9% GST on the discounted price. What was the original price of the television set?
|
Percent expressed as units |
Percent expressed as % |
Amount |
Original price |
100 u |
|
? |
Discount |
- 20 u |
|
|
Discounted price |
80 u |
100% |
$400 |
GST |
|
+ 9% |
|
Amount to pay |
|
109% |
$436 |
Price of the television set with 9% GST in percent
= 100% + 9%
= 109%
109% of the television set with 9% GST = 436
1% of the television set with 9% GST = 436 ÷ 109 = 4
100% of the television set with 9% GST = 100 x 4 = 400
Price of the television set at 20% discount in units
= 100 u - 20 u
= 80 u
Discounted price = 100% of the price to pay for before adding GST.
80 u of the television set without GST = 400
1 u of the television set without GST = 400 ÷ 80 = 5
100 u of the television set without GST = 100 x 5 = 500
Original price of the television set = $500
Answer(s): $500