Question

13分之8✖️9分之7+13分之7✖️9分之5简便运算ĆĆĆ

13分之8乘9分之7加13分之7乘9分之5简便计算2012乘2013分之3简便7分之五-9分之五乘7分之5简便

Answer 1

1)
=7/13×8/9 +7/13×5/9
=7/13×(8/9+5/9)
=7/13×13/9
=7/9
2)
=(2013-1)×3/2013
=2013×3/2013 -1×3/2013
=3-3/2013
=2又2010/2013
3)5/7-5/7×5/9
=5/7×(1-5/9)
=5/7×4/9
=20/63