初一数学的混合运算的简便计算题

计算题:
(1)23+(-73)
(2)(-84)+(-49)
(3)7+(-2.04)
(4)4.23+(-7.57)
(5)(-7/3)+(-7/6)
(6)9/4+(-3/2)
(7)3.75+(2.25)+5/4
(8)-3.75+(+5/4)+(-1.5)

先算乘除再算加减

1. 1+2+3+4+......+100000=?

2. 1/1+1/2+1/3+......1/50=?

3. 1+1/2+1/4+1/8+1/16+......1/512=?

4. +3+9+27+81+243+......9999=?

5. 1+1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72+1/90=?

题目呢?