原式=3/4×6/13+3/4×7/13
=3/4×(6/13+7/13)
=3/4×1
=3/4
希望能够帮到你!!
0.75=3/4
3/4×6/13+3/4×7/13=(3×6+3×7)/(4*13)=(3*13)/(4*13)=3/4=0.75
0.75×6/13+3/4×7/13
=3/4×6/13+3/4×7/13
=3/4×(6/13+7/13)
=3/4×1
=3/4
0.75×6/13+3/4×7/13
=3/4×6/13+3/4×7/13
=3/4×(6/13+7/13)
=3/4