Question

4+3.6Ⅹ=12.1的解释

计算下面各题．（能简算的要简算） 2.5×33×40 32.4+3.6×（12-1.2） 31.2×4+19.8×4 7.2÷[1.8×（3.4-2.9）] 72×0.03+0.3×2.8 28.96-（5.75+8.96）

Answer 1

（1）2.5×33×40
=2.5×40×33
=100×33
=3300
（2）32.4+3.6×（12-1.2）
=32.4+3.6×10.8
=32.4+38.88
=71.28
（3）31.2×4+19.8×4
=（31.2+19.8）×4
=51×4
=204
（4）7.2÷[1.8×（3.4-2.9）]
=7.2÷[1.8×0.5]
=7.2÷0.9
=8
（5）72×0.03+0.3×2.8
=7.2×0.3+0.3×2.8
=（7.2+2.8）×0.3
=10×0.3
=3
（6）28.96-（5.75+8.96）
=28.96-8.96-5.75
=20-5.75
=14.25