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👨🏻‍🏫 學術台數學

Edward

2007-11-01 5:31 am

y(1+40%)(1-a%)-y
--------------------------x100% =12%
y

點計我要公識
a=?
a=?

回答 (2)

tommy

2007-11-01 5:41 am

✔ 最佳答案

[y(1+40%)(1-a%)-y]/yx100% =12%
{y[(1.4)(1-a%)-1]}/y =0.12
1.4(1-a%)-1=0.12
1.4(1-a%)=1.12
1-a%=1.12/1.4
1-a%=0.8
1-0.8=a%
a%=0.2
a=20

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sunny1314758

2007-11-01 5:46 am

[y(1+40%)(1-a%)-y]/yx100% =12%
{y[(1.4)(1-a%)-1]}/y =0.12
1.4(1-a%)-1=0.12
1.4(1-a%)=1.12
1-a%=1.12/1.4
1-a%=0.8
1-0.8=a%
a%=0.2
a=20

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