13.6x42.3x3.75—12.5x0.423x28
问题描述：
13.6x42.3x3.75—12.5x0.423x28
16x14.97÷1996
75x4.67+17.9x2.5
19.98x37+199.8x2.3+9.99x80
1.01+1.04+1.07+···+3.98
0.1+0.3+0.5+···+19.7+19.9
6.03+6.06+6.09+···7.95
0.02+0.04+0.06+0.08+···+0.22+0.24+···+0.96+0.98
答
13.6x42.3x3.75—12.5x0.423x28=42.5*(13.6*15/4-4.5)=42.5*(3.4*15-4.5)=42.5*46.5=44.5^2-4=1976.2516x14.97÷1996=4*14.96/499=5984/4990075x4.67+17.9x2.5=25*(14.01+1.79)=25*15.8=1580/4=39519.98x37+199.8x2....