Question

3.4×2.5×1.8的简便计算？

Answer 1

3.4x2.5ⅹ1.8
=17ⅹ0.2ⅹ2.5ⅹ9ⅹ0.2
=(1.7x0.9)ⅹ(2.5x0.2ⅹ0.2)
=1.7x(10-1)x1
=17-1.7
=15.3

Answer 2

3.4x2.5ⅹ1.8
=3.4ⅹ(2+0.5)ⅹ1.8
=(6.8+1.7)x(1+0.8)
=8.5ⅹ1+8.5ⅹ0.8
=8.5+6.8
=15.3

Answer 3

3.4×2.5×1.8
=3.4×2.5×(2－0.2)
=3.4×(2.5×2－2.5×0.2)
=3.4×(5－0.5)
=3.4×5－3.4×0.5
=17－1.7
=15.3

Answer 4

3.4×2.5×1.8
=（3+0.4）×2.5×1.8
=（3×2.5+1）×1.8
=8.5×1.8
=8.5×（2-0.2）
=8.5×2-8.5×0.2
=17-1.7
=15.3

Answer 5

3.4×2.5×1.8
=17×0.2×2.5×2×0.9
=(17×0.9)×(0.2×2.5×2)
=15.3×1
=15.3