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1.)miss lee buys a carton of milk for $10.2 at a discountof 15%.Find the marked price of the milk.

10.2 / (1-15%) = 12

2.)the marked price of a television is $4000.If an extra discount of 30% is
given on that television sold at 20% off , find
(a)the selling price of the television.
4000 * (1-0.3) * (1-0.2)=2240


(b)the actual discount of the television.

4000-2240=1760


3.)happy department store is holding a sale , an extra discount of 30% is given
on all products sold at 10% off.
(a)Find the selling price of an electric appliance with the marked price of
$900.

900 * 0.7 * 0.9 = 567
(b)What is the actual percentage discount of the above electric appliance
(900-567)/(900)*100%=37%