A furniture store was having Chinese New Year discount of 10% off its usual price. The GST is at 3%. Anna used her credit card to purchase a sofa bed and Japheth used cash to pay for a similar sofa bed.

1. How much did Anna pay in the end after GST? Round off your answer to the nearest cent.
2. How much did Japheth pay in the end after GST? Round off your answer to the nearest ten cent.

New sofa bed Usual Price: $300

Further Discount: Pay by credit card: 10% off discounted price before GST! Pay by cash: $15 off discounted price before GST!

	Credit Card	Cash
Usual Price	$300	$300
Less 10% discount	- $30.00	- $30.00
Price after 10% discount	$270.00	$270.00
Less further discount	- $27.00	- $15
Price after further discount	$243.00	$255.00
Price after GST of 3%	$250.29	$262.70

(a)
New selling price after 10% discount
= 100% - 10%
= 90%

Price of the sofa bed after Chinese New Year discount
= 90% x 300
= ⁹⁰₁₀₀ x 300
= $270.00

New selling price after 10% further discount
= 100% - 10%
= 90%

Price of the sofa bed after credit card discount
= 90% x 270.00
= ⁹⁰₁₀₀ x 270.00
= $243.00

Price to pay after including GST
= 100% + 3%
= 103%

Price of the sofa bed after GST
= 103% x 243.00 
= ¹⁰³₁₀₀ x 243.00 
≈ $250.29 (Round off to nearest cent)

(b)
Price of the sofa bed after cash discount
= 270.00 - 15
= $255.00

Price of the sofa bed after GST
= 103% x 255.00 
= ¹⁰³₁₀₀ x 255.00 
≈ $262.70 (Round off to nearest ten cent)

Answer(s): (a) $250.29; (b) $262.70