例如 100+10%就=110 但係再-10%會變99 即係100+10%再-10%=99
咁A+20%=780000,咁A=?
數學百份率問題
2007-10-17 11:55 pm
回答 (3)
2007-10-18 12:29 am
✔ 最佳答案
A=650000原理很簡單只要你明白了就知道怎麼算了
如:一件衫$100如加價10%你知道加價後的衫是$110
$100(原價)+$100*10%(加價的幅度)=$110(加價後的價)
你的問題是怎樣求A=原價是多少?
計算方法如下
A+A*20%=780000
A(1+20%)=780000
A=780000/(1+0.2)
A=650000
2007-10-18 12:23 am
100+10%
=> 100 * (1 + 10%)
= 100 * (1 + 10/100)
= 100 * 1.1
= 110
110-10%
=> 110 * (1 - 10%)
= 110 * (1 - 0.1)
= 110 * 0.9
= 99
A+20% = 780000
=> A * (1 + 20%) = 780000
=> A * 1.2 = 780000
=> A = 780000 / 1.2 = 650000
=> 100 * (1 + 10%)
= 100 * (1 + 10/100)
= 100 * 1.1
= 110
110-10%
=> 110 * (1 - 10%)
= 110 * (1 - 0.1)
= 110 * 0.9
= 99
A+20% = 780000
=> A * (1 + 20%) = 780000
=> A * 1.2 = 780000
=> A = 780000 / 1.2 = 650000
2007-10-18 12:06 am
A(1+20%)=780000
1.2A=780000
A=780000/1.2
A=650000
1.2A=780000
A=780000/1.2
A=650000
收錄日期: 2021-04-13 18:50:58
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071017000051KK01619