27-(-2)-19
-12-(50)-14.5
13+(4.2)+(+8)-7.8
think
有向數~~
2006-10-24 1:32 am
回答 (5)
2006-10-24 1:35 am
✔ 最佳答案
1.27 - (-2 ) - 19
= 27 + 2 - 19
= 10
2.
-12 - (50) - 14.5
= -12 - 50 - 14.5
= -62 - 14.5
= - 76 .5
3.
13 + 4.2 + 8 - 7.8
= 25.2 - 7.8
= 17 . 4
2006-10-24 1:48 am
Rules:
正正得正
正負得負
負正得負
負負得正
27-(-2)-19 =
27 + 2 - 19 = ….(負負得正)
10
-12-(50)-14.5 =
-12 -50 - 14.5 = ….(負正得負)
-76.5
13+(4.2)+(+8)-7.8 =
13 + 4.2 + 8 -7.8 = ….(正正得正)
17.4
正正得正
正負得負
負正得負
負負得正
27-(-2)-19 =
27 + 2 - 19 = ….(負負得正)
10
-12-(50)-14.5 =
-12 -50 - 14.5 = ….(負正得負)
-76.5
13+(4.2)+(+8)-7.8 =
13 + 4.2 + 8 -7.8 = ….(正正得正)
17.4
2006-10-24 1:46 am
算這些數一定要注意同號得正,異號得負
即是正正得正,正負得負,負正得負,負負得正
士(士a)=+a
士(干a)=-a
干(士a)=-a
還有,兩數相減,如27-63,不夠減,就要變成-(63-27)=-36
兩個負數相加,即是它們的相反數相加的相反數,即是-a+(-b)=-a-b=-(a+b)
27-(-2)-19
=27+2-19
=29-19
=10
-12-(50)-14.5
=-12-50-14.5
=-62-14.5
=-76.5
13+(4.2)+(+8)-7.8
=13+4.2+8-7.8
=17.2+2
=19.2
即是正正得正,正負得負,負正得負,負負得正
士(士a)=+a
士(干a)=-a
干(士a)=-a
還有,兩數相減,如27-63,不夠減,就要變成-(63-27)=-36
兩個負數相加,即是它們的相反數相加的相反數,即是-a+(-b)=-a-b=-(a+b)
27-(-2)-19
=27+2-19
=29-19
=10
-12-(50)-14.5
=-12-50-14.5
=-62-14.5
=-76.5
13+(4.2)+(+8)-7.8
=13+4.2+8-7.8
=17.2+2
=19.2
2006-10-24 1:43 am
you want answer?or ask how to do?
1. 27-(-2)-19
=27+2-19
=10
2. -12-(50)-14.5
= -12-50-14.5
= -62-14.5
=76.5
3. 13+(4.2)+(+8)-7.8
= 13+4.2+8-7.8
=17.2+8-7.8
=25.2-7.8
=17.4
1. 27-(-2)-19
=27+2-19
=10
2. -12-(50)-14.5
= -12-50-14.5
= -62-14.5
=76.5
3. 13+(4.2)+(+8)-7.8
= 13+4.2+8-7.8
=17.2+8-7.8
=25.2-7.8
=17.4
2006-10-24 1:36 am
1.
27-(-2)-19
=27+2-19
=10
2.
-12-(50)-14.5
=-12-50-14.5
=-(12+50+14.5)
=-76.5
3.
13+(4.2)+(+8)-7.8
=13+4.2+8-7.8
=17.4
27-(-2)-19
=27+2-19
=10
2.
-12-(50)-14.5
=-12-50-14.5
=-(12+50+14.5)
=-76.5
3.
13+(4.2)+(+8)-7.8
=13+4.2+8-7.8
=17.4
參考: Calculation
收錄日期: 2021-04-12 18:10:27
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