Question

这些题怎么做

Answer 1

(4)-3+5-8

=2-8
=-6
(5).1-2+3-4+5-6+......+99-100
=(1-2)+(3-4)+(5-6)+......+(99-100)
=(-1)+(-1)+(-1)+......+(-1)
=-50
(6). -17+17-26
=0-26
=-26
(7). 1-4+3-0.5
=-3+3-0.5
=-0.5
(8).-2.4+3.5-4.6+3.5
=(-2.4-4.6)+(3.5+3.5)
=-7+7
=0
(9). 3-32又1/2-5又1/4-(-3又1/7)+3.25+2又6/7-(-28又1/2)
=3-32又1/2-5又1/4+3又1/7+3又1/4+2又6/7+28又1/2
=3+(-32又1/2+28又1/2)+(-5又1/4+3又1/4)+(3又1/7+2又6/7)
=3-4-2+6
=-3+6
=3
(10). 3/4-7/2+(-1/6)-(-2/3)-1
=3/4-3又1/2-1/6+2/3-1
=3/4-3-1/2+(-1/6+4/6)-1
=3/4-3-1/2+1/2-1
=3/4-3-1
=3/4-4
=-3又1/4

Answer 2

图

追答