A furniture store was having National Day discount of 20% off its usual price. The GST is at 7%. Esther used her credit card to purchase a kitchen table and Seth used cash to pay for a similar kitchen table.

1. How much did Esther 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 kitchen table Usual Price: $1900

Further Discount: Pay by credit card: 10% off discounted price before GST! Pay by cash: $100 off discounted price before GST!

	Credit Card	Cash
Usual Price	$1900	$1900
Less 20% discount	- $380.00	- $380.00
Price after 20% discount	$1520.00	$1520.00
Less further discount	- $152.00	- $100
Price after further discount	$1368.00	$1420.00
Price after GST of 7%	$1463.76	$1519.40

(a)
New selling price after 20% discount
= 100% - 20%
= 80%

Price of the kitchen table after National Day discount
= 80% x 1900
= ⁹⁰₁₀₀ x 1900
= $1520.00

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

Price of the kitchen table after credit card discount
= 90% x 1520.00
= ⁹⁰₁₀₀ x 1520.00
= $1368.00

Price to pay after including GST
= 100% + 7%
= 107%

Price of the kitchen table after GST
= 107% x 1368.00 
= ¹⁰⁷₁₀₀ x 1368.00 
≈ $1463.76 (Round off to nearest cent)

(b)
Price of the kitchen table after cash discount
= 1520.00 - 100
= $1420.00

Price of the kitchen table after GST
= 107% x 1420.00 
= ¹⁰⁷₁₀₀ x 1420.00 
≈ $1519.40 (Round off to nearest ten cent)

Answer(s): (a) $1463.76; (b) $1519.40