A furniture store was having Grand Opening discount of 25% off its usual price. The GST is at 6%. Betty used her credit card to purchase a study table and Seth used cash to pay for a similar study table.

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

New study table Usual Price: $720

Further Discount: Pay by credit card: 5% off discounted price before GST! Pay by cash: $95 off discounted price before GST!

	Credit Card	Cash
Usual Price	$720	$720
Less 25% discount	- $180.00	- $180.00
Price after 25% discount	$540.00	$540.00
Less further discount	- $27.00	- $95
Price after further discount	$513.00	$445.00
Price after GST of 6%	$543.78	$471.70

(a)
New selling price after 25% discount
= 100% - 25%
= 75%

Price of the study table after Grand Opening discount
= 75% x 720
= ⁹⁵₁₀₀ x 720
= $540.00

New selling price after 5% further discount
= 100% - 5%
= 95%

Price of the study table after credit card discount
= 95% x 540.00
= ⁹⁵₁₀₀ x 540.00
= $513.00

Price to pay after including GST
= 100% + 6%
= 106%

Price of the study table after GST
= 106% x 513.00 
= ¹⁰⁶₁₀₀ x 513.00 
≈ $543.78 (Round off to nearest cent)

(b)
Price of the study table after cash discount
= 540.00 - 95
= $445.00

Price of the study table after GST
= 106% x 445.00 
= ¹⁰⁶₁₀₀ x 445.00 
≈ $471.70 (Round off to nearest ten cent)

Answer(s): (a) $543.78; (b) $471.70