30×20×y＝12.8×10
56×2.5＋(56＋y)×2.5＝300
3.5×七分之二十二×y＋32＝1000
計極都計唔明>.
數學題(方程式)~
2007-06-01 11:44 pm
回答 (6)
2007-06-01 11:53 pm
✔ 最佳答案
30x20xy=12.8x10是等於600xy=128，若把128除以600，便能求得y所以y=128/600=16/75
2007-06-01 16:05:19 補充：
以上是第一題答案2.(56+y)x2.5等於56x2.5+2.5y，所以56x2.5+(56+y)x2.5=56x2.5+56x2.5+2.5y=56x2.5x2+2.5y=300 y=(300-56x2.5x2)/2.5y=83. 3.5x22y/7等於77y/7等於11y 所以y=(1000-32)/11 =1968/11 =178 10/11
2007-06-02 3:40 am
30×20×y＝12.8×10
600y=128
y=128/600
y=16/75
56×2.5＋(56＋y)×2.5＝300
130+130+2.5y=300
2.5y=40
y=16
3.5×七分之二十二×y＋32＝1000
11y+32=1000
11y=1000--32
11y=968
y=88
600y=128
y=128/600
y=16/75
56×2.5＋(56＋y)×2.5＝300
130+130+2.5y=300
2.5y=40
y=16
3.5×七分之二十二×y＋32＝1000
11y+32=1000
11y=1000--32
11y=968
y=88
參考: 自己
2007-06-01 11:59 pm
30×20×y＝12.8×10
y = (12.8 x 10) / (30 x 20) = 16 / 75
56×2.5＋(56＋y)×2.5＝300
(56＋y)×2.5 = 300 - 26x2.5
(56＋y)×2.5 = 235
56 + y = 235 / 2.5
56 + y = 94
y = 38
3.5×七分之二十二×y＋32＝1000
3.5 x 22y/7 + 32 = 1000
3.5 x 22y/7 = 1000 - 32
3.5 x 22y/7 = 968
35/100 x 22y/7 = 968
11y/100 = 968
y = 968 x 100/11 = 8800
y = (12.8 x 10) / (30 x 20) = 16 / 75
56×2.5＋(56＋y)×2.5＝300
(56＋y)×2.5 = 300 - 26x2.5
(56＋y)×2.5 = 235
56 + y = 235 / 2.5
56 + y = 94
y = 38
3.5×七分之二十二×y＋32＝1000
3.5 x 22y/7 + 32 = 1000
3.5 x 22y/7 = 1000 - 32
3.5 x 22y/7 = 968
35/100 x 22y/7 = 968
11y/100 = 968
y = 968 x 100/11 = 8800
2007-06-01 11:56 pm
1)60y=128
60y/60=128/60
y=2 2/15
2)140+140+2.5y=300
140+140+2.5y-280=300-280
2.5y/2.5=20/2.5
y=8
3)11y+32-32=1000-32
11y/11=968/11
y=88
60y/60=128/60
y=2 2/15
2)140+140+2.5y=300
140+140+2.5y-280=300-280
2.5y/2.5=20/2.5
y=8
3)11y+32-32=1000-32
11y/11=968/11
y=88
2007-06-01 11:52 pm
1. y=32/150
2. y=8
3. y=8.8
2. y=8
3. y=8.8
收錄日期: 2021-05-01 10:06:55
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070601000051KK01884