Question

19×括号1/19+1/31括号乘3等于多少，简便计算

19×括号1/19+1/31括号乘3等于多少，简便计算

Answer 1

19×括号1/19+1/31括号乘3等于多少，简便计算
解：采用分配律，
原式=19x（1/19+1/31）X3
=19X1/19x3+19x1/31x3
=3+57/31
=3+1+26/31
=4又26/31

Answer 2

19×（1/19+1/31）×3
=（19×1/19+19×1/31）×3
=（1+19/31）×3
=1×3+19/31×3
=3+57/31
=91/31+57/31
=148/31