-4.25-(-6又1/7+(-5.75)-(-2又3/14）
=-4.25+43/7+5.75+31/14
=(5.75-4.25)+(43/7+31/14)
=1.5+(86+31)/14
=3/2+117/14
=21/14+117/14
=138/14
=69/7