Question

七分之五加十四分之九加二十一分之八简便运算i

七分之五加十四分之九加二十一分之八简便运算i

Answer 1

5/7 + 9/14 +8/21
=15/21+8/21 +9/14
=23/21 +9/14
=1+ 2/21 +9/14
=1+ 4/42 +27/42
=1+ 31/42
=1又31/42