5.7×1.42-5.7×4.2等于多少简便计算？ 5.8+4.2 2.05简便计算

• 4.2*1.2-5.2*0.7 怎么简便计算
• (5.7×1.2 1.2×4.3)×2.5怎样简便就怎样计算?
• 4.8×5.7+0.48×42+4.8的简便计算
• 4.2*1.2+5.2*0.7怎么用简便方法计算

4.2*1.2-5.2*0.7 怎么简便计算

0.7*6*1.2-5.2*0.7

=（7.2-5.2）*0.7

=2*0.7

=1.4

(5.7×1.2 1.2×4.3)×2.5怎样简便就怎样计算?

(5.7×1.2 +1.2×4.3)×2.5

=1.2×（5.7+4.3）×2.5

=1.2×10×2.5

=1.2×2.5

=3×（0.4×2.5）

=3×1

=3

4.8×5.7+0.48×42+4.8的简便计算

4.8×5.7+0.48×42+4.8

=4.8x(5.7+4.2+1)

=4.8x10.9

=4.8x10+4.8x0.9

=48+4.8x1-4.8x0.1

=48+4.8-0.48

=52.32

4.2*1.2+5.2*0.7怎么用简便方法计算

4.2*(1.3-0.1)+(4.2+1)*0.7=(0.7+1.3)*4.2+0.7-0.42=8.68