A furniture store was having Year End discount of 30% off its usual price. The GST is at 4%. Wendy used her credit card to purchase a sofa set and Reggie used cash to pay for a similar sofa set.

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

New sofa set Usual Price: $750

Further Discount: Pay by credit card: 10% off discounted price before GST! Pay by cash: $55 off discounted price before GST!

	Credit Card	Cash
Usual Price	$750	$750
Less 30% discount	- $225.00	- $225.00
Price after 30% discount	$525.00	$525.00
Less further discount	- $52.50	- $55
Price after further discount	$472.50	$470.00
Price after GST of 4%	$491.40	$488.80

(a)
New selling price after 30% discount
= 100% - 30%
= 70%

Price of the sofa set after Year End discount
= 70% x 750
= ⁹⁰₁₀₀ x 750
= $525.00

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

Price of the sofa set after credit card discount
= 90% x 525.00
= ⁹⁰₁₀₀ x 525.00
= $472.50

Price to pay after including GST
= 100% + 4%
= 104%

Price of the sofa set after GST
= 104% x 472.50 
= ¹⁰⁴₁₀₀ x 472.50 
≈ $491.40 (Round off to nearest cent)

(b)
Price of the sofa set after cash discount
= 525.00 - 55
= $470.00

Price of the sofa set after GST
= 104% x 470.00 
= ¹⁰⁴₁₀₀ x 470.00 
≈ $488.80 (Round off to nearest ten cent)

Answer(s): (a) $491.40; (b) $488.80