Question

简便。1/5x0.25加4/5×25%怎么做？15/17÷8+2/17×1/8怎么做？7.5×8/

简便。1/5x0.25加4/5×25%怎么做？15/17÷8+2/17×1/8怎么做？7.5×8/7-1/7×7.5怎么做？12×1/2+1/4-1/6怎么做？2/3-4/7的和乘以21怎么做？

Answer 1

这样

追答

追问

谢谢大哥

7.5×8/7-1/7×7.5怎么做？

谢谢大哥哥！

三分之二减七分之四乘以二十一怎么做？十一点七加三分之二加三点三加三分之一怎么做？快点！谢谢大哥！

追答

Answer 2

1/5x0.25+4/5×25%
=1/5x1/4+4/5×1/4
=(1/5+4/5)×1/4
=1×1/4
=1/4
15/17÷8+2/17×1/8
=15/17×1/8+2/17×1/8
=(2/17+15/17)×1/8
=1×1/8
=1/8
7.5×8/7-1/7×7.5
=7.5×(8/7-1/7)
=7.5×1
=7.5
12×1/2+1/4-1/6

=6+(1/4-1/6)
=6+(3/12-2/12)
=6+1/12
=6又1/12
(2/3-4/7)×21
=2/3×21-4/7×21
=14-12
=2

追问

11.7+2/3+3.3+1/3怎么做？

追答

11.7+2/3+3.3+1/3
=(11.7+3.3)+(2/3+1/3)
=15+1
=16