29.7-(6.2+0.84)*4 简便运算
问题描述：
29.7-(6.2+0.84)*4 简便运算
答
29.7-4*6.2+4*0.84
答
29.7-(6.2+0.84)*4
=29.7-7.04*4
=29.7-(7+0.04)*4
=29.7-7*4-0.04*4
=29.7-28-0.16
=1.7-0.16
=1.54