Question

请问这两题计算题怎么写？

请问这两题计算题怎么写？

Answer 1

1.5+2.5*12.7
=1.5+2.5*3*4+2.5*0.7
=1.5+10*3+2.5*0.4+2.5*0.4-0.1*2.5
=1.5+30+1+1-0.25
=33.5-0.25
=33.25
6.8*2.05-2.8*0.45
=4*2.05+2.8*2.05-2.8*0.45
=8.2+2.8*(2.05-0.45)
=8.2+2.8*1.6
=8.2+2.5*1.6+0.3*1.6
=8.2+2.5*4*0.4+0.48
=8.2+4+0.48
=8.68+4
=12.68

Answer 2

1.5+2.5×12.7
＝1.5+2.5×（10+2+0.7）
＝1.5+2.5×10+2.5×2+2.5×0.7
＝1.5+25+5+（2+0.5）×0.7
＝1.5+30+1.4+0.35
＝33.25
6.8×2.05-2.8×0.45
＝（2.8+4）×2.05-2.8×0.45
＝2.8×（2.05-0.45）+4×2.05
＝2.8×1.6+4×2.05
＝4× 0.7×1.6+4×2.05
＝4×（1.12+2.05）
＝4×3.17
＝12.68

Answer 3

5+2.5×12.7
＝5+31.75
＝36.75

Answer 4

用计算机。。。。

Answer 5

额😓，2.5x12.7=31.75 加上1.5得33.25
6.8X2.05=13.94 2.8X0.45=1.26
相减得12.68。。。。。。。