括号乘49加72乘51加34乘49,括号填什么能简便

问题描述:

括号乘49加72乘51加34乘49,括号填什么能简便

填38:
( 38)*49+72*51+34*49
=(38+34)*49+72*51
=72*49+72*51
=72*(49+51)
=72*100
=7200

(38)×49+72×51+34×49=7200.