18*222.2-666.6的答案中有222.2×(18-3),为什么要×(18-3)

问题描述:

18*222.2-666.6的答案中有222.2×(18-3),为什么要×(18-3)

× = * ,都是乘号.
666.6 =3* 222.2
18*222.2 -666.6 = 18*222.2 - 3*222.2 = (18-3)*222.2