<40 marks> 各位知識朋友 , 入黎幫我手 ar !!! ( 數學F.1 ) (71)

1.A jacket is sold for $375.The percentage profit is 25%.Whant is the
cost price of the jacket?
Let the cost price be $x
x(1+25%)=375
1.25x=375
x=300

2.The profit on selling an article is 44% of its cost price.If the profit is
$1056,find the selling price of the article.
Let the cost price be $x
the profit is 44%x=0.44x
0.44x=1056
x=2400
the selling price=2400+1056=$3456
3.After 15% of a bill has been deducted,$782 remains to be paid.Howmuch was the original bill.
Let the original bill be $x
(1-15%)x=782
0.85x=782
x=920

1. The cost price of the jacket:

375 / (1-25%)

= $300


2. The selling price of the article:

(1056 / 44%) 1056

=2400 1056

=$3456


3.The cost of the original bill:

782 / (1-15%)

=782 / 85%

=$920