Question

用简便方法计算1/5*25.6*13+24.4*0.2*3-13*40*1/5

麻烦看清题目
24.4*0.2*3不是13
正确答案是22.8，怎么算？？

Answer 1

1/5*25.6*13+24.4*0.2*13-13*40*1/5
=1/5×25.6×13+24.4×13×1/5-13×40×1/5
=1/5×13（25.6+24.4-40）
=13/5×60
=13*12
=156

Answer 2

1/5*25.6*13+24.4*0.2*3-13*40*1/5
=1/5*25.6*13-13*40*1/5+24.4*0.2*3
=0.2*13*(25.6-40)+24.4*0.2*3
=-0.2*13*24.4+24.4*0.2*3
=0.2*24.4*(-13+3)
=0.2*24.4*(-10)
= -48.8

Answer 3

1/5*25.6*13+24.4*0.2*13-13*40*1/5
=1/5×25.6×13+24.4×13×1/5-13×40×1/5
=1/5×13（25.6+24.4-40）
=13/5×60
=13*12
=156

Answer 4

n = 1 / 5 * 25.6 * 13 + 24.4 * 0.2 * 3 - 13 * 40 * 1 / 5
n输出 : -22.8

用电脑算的，秒杀一切解法

Answer 5

000