Gillian bought one laptop at 20% discount off its original price. She paid a total of $880 for it, which was inclusive of 10% GST on the discounted price. What was the original price of the laptop?
|
Percent expressed as units |
Percent expressed as % |
Amount |
Original price |
100 u |
|
? |
Discount |
- 20 u |
|
|
Discounted price |
80 u |
100% |
$800 |
GST |
|
+ 10% |
|
Amount to pay |
|
110% |
$880 |
Price of the laptop with 10% GST in percent
= 100% + 10%
= 110%
110% of the laptop with 10% GST = 880
1% of the laptop with 10% GST = 880 ÷ 110 = 8
100% of the laptop with 10% GST = 100 x 8 = 800
Price of the laptop 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 laptop without GST = 800
1 u of the laptop without GST = 800 ÷ 80 = 10
100 u of the laptop without GST = 100 x 10 = 1000
Original price of the laptop = $1000
Answer(s): $1000