用简便方法计算.30*(3⼀10+7⼀15),2又1⼀2*4⼀15+1⼀3*5⼀2+2⼀5*5⼀2,4⼀5*3⼀8*5⼀4,5⼀8*4+5⼀8*3+5⼀8

2024-11-20 00:25:31
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回答1:

1/5+7/15+4/15 =3/15+7/15+4/15 =14/15 7/10-(3/4-2/5)=1-27/99+55/99 =1+28/99 =1又28/99 请在4天内发给我!!! ..