2分之1×(-2009)+(-2009)×3分之1+2005×6分之5

问题描述:

2分之1×(-2009)+(-2009)×3分之1+2005×6分之5

2分之1×(-2009)+(-2009)×3分之1+2005×6分之5
=-2009×(1/2+1/3)+2005×5/6
=-2009×5/6+2005×5/6
=5/6×(-2009+2005)
=5/6×(-4)
=-10/3