题目

1、列式计算：负6又三分之二 的绝对值的四分之一 除以负五分之二 的2倍所得的商.
2、计算：四分之三*（-7）-（-15）*一又四分之三-0.75*2
3、计算：（-1）的50次方+（-2）的三次方+负二分之一的五次方+（-1）的七次方
4、解下列方程：80% + 60% (500 – x ) = 500×70%
5.求不等式组 ｛x-(4x-1)＜7的整数解.
｛2x+1分之3 - x分之2≤1
6、解方程组 ｛ -6x+5y-3z=-4
｛ 6x-3y+z=8
｛ 6x+y+4z=9
7、三角形三边之比为 2∶3∶4,最长一边比其余两条边之和短4厘米,求三角形的周长
8、一件工程,甲单独做8天完成,甲、乙两人合作5天可完成,甲、丙两人合作4天可完成,求甲、乙、丙三人合作,几天可完成?
9、某次数学测验,两个班级合格率是81%,如果一班的合格率是71%,二班的合格率是90%,两班人数是95人,求两个班人数各是多少人?
10、算式 1× (- 2) × 3 × (- 4) × … × 29 × (- 30) 的积的末尾有多少个零?
It was Jane’s birthday.It was seven o’clock.Everything was ready.Her mother was cooking in the kitchen and her father was still at work.On the table,there were many different kinds of food.And in the middle of the table there was a very big cake.13 candles were on the cake.Jane was looking at it,and felt excited.“Why haven’t they come by now?I told them to come at seven.” Jane said to her mother worriedly.One,two,three ...twenty-five minutes passed.But no one came.Jane

提问时间：2021-01-05

答案

1. |-6又2/3|*1/4/（（-2/5）*2）=-25/122. （3/4）*（-7）-（-15）*(1又3/4)-0.75*2 =-21/4+105/4+3/2 =39/23. (-1)^50次方+(-2)^3次方+(-1/2)^5次方+(-1)^7次方 =1+(-8)+(-1/32)+(-1) =-257/324解 0.8+3...