(-2)的4次方÷（-2又3分之2）²+5又2分之1×（-6分之1）-0.25
=16÷（-8/3）²+11/2×（-1/6）-1/4
=16×9/64-11/12-1/4
=9/4-11/12-1/4
=2-11/12
=13/12