E作者kimoqueen (AT苦海何时能解脱~ @_@)
看板GMAT
标题[计量] 请问一题数学
时间Tue Dec 16 15:37:20 2008
After paying a 12.5 percent tax on all income in excess of $4000
for the year, Simon had a net annual income of $21500.
What was his average income per month before taxes?
请问计算过程是如下: (不好意思，我计算很弱才死在这@@)
x-(x-4000)*0.125=21500
x-0.125x+500=21500
0.875x=21000(就是卡在这,我老是算错@@)
x=24000 再除12=2000
答案是2000没错...
麻烦各位大大，谢谢~
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※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 59.121.128.95
1F：推 surfingdream:设X总income,X-(X-4000)*(0.125)=21500,求出X 12/16 15:56
2F：→ surfingdream:再除以12,这样算出来对吗? 12/16 15:57
3F：推 Chest:楼上正解 12/16 15:57
4F：→ Chest:顺带一提，答案是2,000 12/16 15:58
5F：→ surfingdream:看错,还要再加回扣掉的部份(X-4000)*0.125 12/16 15:59
6F：→ surfingdream:加回之後再除以12,应该就对了吧 12/16 15:59
※ 编辑: kimoqueen 来自: 59.121.128.95 (12/16 16:10)
7F：推 dvsmatix:不用加回吧? 12/16 16:09
8F：→ Vinicks:S大 不用回减 用你第一个公式就算出24000 在除12就是2000 12/16 16:10
9F：→ Vinicks:4000*0.125是500 你就错在这边 答案X等於24000 要再除12喔 12/16 16:11
※ 编辑: kimoqueen 来自: 59.121.128.95 (12/16 16:14)
10F：→ kimoqueen:谢谢各位回覆 ^^ 我会再小心一点的... @@ 12/16 16:16
11F：推 surfingdream:嗯嗯～～～想太多了 >< 12/16 16:29