19.8乘0.48用简便方法计算
问题描述:
19.8乘0.48用简便方法计算
答
19.8*0.48
=(20-0.2)*(0.5-0.02)
=20*0.5-20*0.02-0.2*0.5+0.2*0.02
=10-0.4-0.1+0.004
=9.504