三道无敌简单的初一有理数计算题(1)(1/2-1/4+1/5)×20(2)71又16/15×(-8)(3)-12又1/9×9
问题描述：
三道无敌简单的初一有理数计算题
(1)(1/2-1/4+1/5)×20
(2)71又16/15×(-8)
(3)-12又1/9×9
答
(1),9
(2),-8648/15
(3),-108
答
1.9
2.-576又8/15
3.－109
答
哇塞 无敌简单 还发上来
0 0.。
答
9
-8648/15
-108
答
(1)(1/2-1/4+1/5)×20
=1/2×20-1/4×20+1/5×20
=10-5+4
=9
(2)71又16/15×(-8)
=(71+15/16)×(-8)
=71×(-8)+15/16×(-8)
=-568-15/2
=-568-7-1/2
=-(575+1/2)
=负575又1/2
(3)-12又1/9×9
=-(12+1/9)×9
=-12×9-1/9×9
=-108-1
=-109
答
(1)(1/2-1/4+1/5)×20=9
(2)71又16/15×(-8)=-576又(8/15)
(3)-12又1/9×9=-109