Question

计算下面各题 .递等式计算.（2/7＋4/21）×7/16 3/4－2/5×3/45555555丶丶丶

Answer 1

(2/7+4/21)×7/16

=2/7×7/16+4/21×7/16

=1/8+1/12

=3/24+2/24

=5/24

3/4-2/5×3/4

=(1-2/5)×3/4

=3/5×3/4

=9/20