A furniture store was having Christmas discount of 10% off its usual price. The GST is at 5%. Emily used her credit card to purchase a breakfast hutch and Bobby used cash to pay for a similar breakfast hutch.

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

New breakfast hutch Usual Price: $640

Further Discount: Pay by credit card: 10% off discounted price before GST! Pay by cash: $60 off discounted price before GST!

	Credit Card	Cash
Usual Price	$640	$640
Less 10% discount	- $64.00	- $64.00
Price after 10% discount	$576.00	$576.00
Less further discount	- $57.60	- $60
Price after further discount	$518.40	$516.00
Price after GST of 5%	$544.32	$541.80

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

Price of the breakfast hutch after Christmas discount
= 90% x 640
= ⁹⁰₁₀₀ x 640
= $576.00

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

Price of the breakfast hutch after credit card discount
= 90% x 576.00
= ⁹⁰₁₀₀ x 576.00
= $518.40

Price to pay after including GST
= 100% + 5%
= 105%

Price of the breakfast hutch after GST
= 105% x 518.40 
= ¹⁰⁵₁₀₀ x 518.40 
≈ $544.32 (Round off to nearest cent)

(b)
Price of the breakfast hutch after cash discount
= 576.00 - 60
= $516.00

Price of the breakfast hutch after GST
= 105% x 516.00 
= ¹⁰⁵₁₀₀ x 516.00 
≈ $541.80 (Round off to nearest ten cent)

Answer(s): (a) $544.32; (b) $541.80