简便算4.6+8.4/2.4 9.9*13.8
问题描述：
简便算4.6+8.4/2.4 9.9*13.8
答
4.6+8.4/2.4
=4.6+3.5
=8,1
9.9*13.8
=(10-0.1)*13.8
=10*13.8-0.1*13.8
=138-1.38
=136.62