The marked price of a digital camera is three times of the cost.
When the digital camera is sold at a certain discount on the marked price,
the percentage profit is20%. Find the discount percentage.
f.4 maths 40marks
2007-07-24 4:55 am
回答 (3)
2007-07-24 5:06 am
✔ 最佳答案
Let the cost be $ x and so the marked price is $ 3x. Suppose the discount % is r%. The selling price : 3x ( 1 - r% )
Then,
( 1 / x ){3x ( 1 - r % ) - x }( 100% ) = 20%
3 ( 1 - r % ) - 1 = 0.2
1 - r% = 0.4
r% = 0.6
r = 60
So the discount % is 60%.
參考: My Maths Knowledge
2007-07-24 5:51 am
Let the cost be $ x and the marked price be $ 3x.
Suppose the discount is r% so the selling price : 3x ( 1 - r% )
( 1 / x ){3x ( 1 - r % ) - x }( 100% ) = 20%
3 ( 1 - r % ) - 1 = 0.2
r = 60
Therefore the discount is 60%.
Suppose the discount is r% so the selling price : 3x ( 1 - r% )
( 1 / x ){3x ( 1 - r % ) - x }( 100% ) = 20%
3 ( 1 - r % ) - 1 = 0.2
r = 60
Therefore the discount is 60%.
2007-07-24 5:05 am
60% off
收錄日期: 2021-05-01 19:33:45
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https://hk.answers.yahoo.com/question/index?qid=20070723000051KK04604