HELP ME YO SOLVE THIS MATHS QUSTION :
30 x ( 1 - r% ) = 20 x ( 1 + r% )
MATHS QUESTION
2007-08-27 8:49 pm
回答 (6)
2007-08-27 9:10 pm
✔ 最佳答案
證明: 30*(1-r%)=20*(1+r%) 30-30r%=20+20 r%
30-20=20r%+30r%
10=50r%
1/5=r%
1/5=1/100r
r=20
驗證(左邊):30*(1-20%)
=30*80%
=30*0.8
=24
(右邊):20*(1+20%)
=20*120%
=20*1.2
=24
參考: 自己
2007-08-27 11:12 pm
30x(1-r/100)=20x(1+r/100)
30-30r/100=20+20r/100
30-0.3r=20+0.2r
0.5r=10
r=20
30-30r/100=20+20r/100
30-0.3r=20+0.2r
0.5r=10
r=20
2007-08-27 8:55 pm
30 -30r =20 +20r
10=50r
r=10/50
r=0.2 %
10=50r
r=10/50
r=0.2 %
2007-08-27 8:54 pm
30 x (1-r%) = 20 x (1+r%)
30-30r% = 20+20r%
30-20=30r%+20r%
50r%=10
r%=0.2
r=20
30-30r% = 20+20r%
30-20=30r%+20r%
50r%=10
r%=0.2
r=20
2007-08-27 8:54 pm
30 x ( 1 - r% ) = 20 x ( 1 + r% )
30 - 30r% = 20 + 20r%
20r% + 30r% = 30 - 20
50r% = 10
50r / 100 = 10
50r = 1000
r = 20
30 - 30r% = 20 + 20r%
20r% + 30r% = 30 - 20
50r% = 10
50r / 100 = 10
50r = 1000
r = 20
2007-08-27 8:53 pm
30 - 0.3r = 20 + 0.2r
10 = 0.5 r
r = 20
10 = 0.5 r
r = 20
收錄日期: 2021-04-13 18:18:40
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070827000051KK01838