1/0.2×【2又2分之1-(-1+2又4分之1)】×0.4
=5×(5/2+1-9/2)×0.4
=5×0.4×(-1)
=-2
3又7分之1×（3又7分之1-7又3分之1）×7/22÷1又25分之1
=22/7×（22/7-22/3）×7/22÷26/25
=22/7×7/22×（22/7-22/3）×25/26
=（22/7-22/3）×25/26
=22（1/7-1/3）×25/26
=22×（-4/21）×25/26
=-22*2*25/(21*13)
=-1100/273