(一)找出未知數(求出下列算式中的a,並作驗算)
2014-04-24 9:44 am
(1)a+165=250(2)a-360=120(3)a+17/6=8又17/6(4)a-5/4=6又5/1(5)a+38+76=205(6)66+a+197=268(7)a+0.16+0.5=1(8)a-1又5/2-3又5/3=4又5/4
回答 (9)
2014-04-24 12:39 pm
✔ 最佳答案
(1) a+165=250a+165-165=250-165a=250-165=85驗算: 85+165=250(2) a-360=120a-360+360=120+360a=120+360=480驗算: 480-360=120
2014-04-24 04:41:52 補充：
(3) a+17/6=8+17/6
a+17/6-17/6=8+17/6-17/6
a=8
驗算: 8+17/6=8+17/6
(4) a-5/4=6又5/1
a-5/4+5/4=6+5/1+5/4
a=6+5+5/4
=11+5/4
=12+1/4
驗算: 12+1/4-5/4
=12-4/4
=12-1
=11
=6+5/1
(5) a+38+76=205
a+38+76-38-76=205-38-76
a=205-114=91
驗算: 91+38+76=91+114=205
2014-04-24 04:53:32 補充：
(6) 66+a+197=268
a+263=268
a+263-263=268-263
a=5
驗算: 66+5+197=268
(7) a+0.16+0.5=1
a+0.66=1
a+0.66-0.66=1-0.66
a=1-0.66=0.34
驗算: 0.34+0.16+0.5=0.34+0.66=1
2014-04-24 04:54:10 補充：
(8) a-1-5/2-3-5/3=4+5/4
4+1+1/4=a-4-5/2-5/3
5+1/4=a-4-2-1-1/2-2/3
=a-7-(3+4)/6
=a-7-7/6
=a-7-1-1/6
=a-8-1/6
5+1/4+8+1/6=a-8-1/6+8+1/6
a=13+1/4+1/6
=13+(3+2)/12
=13+5/12
驗算:
13+5/12-1-5/2-3-5/3
=9+5/12-5/2-5/3
=9+5/12-2-1/2-1-2/3
=6+5/12-1/2-2/3
=6+(5-6-8)/12
=6-9/12
=6-3/4
2014-04-24 04:54:31 補充：
=5+1/4
=4+5/4
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收錄日期: 2021-04-30 18:42:06
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20140424000016KK00725