9分之7乘52加9分之2乘51

问题描述:

9分之7乘52加9分之2乘51

=7/9×(51+1)+2/9×51
=7/9×51+7/9×1+2/9×51
=(7/9+2/9)×51+7/9
=1×51+7/9
=51又9分之7