22/7×21/22×(22/7-22/3)×(-7/22)=?
问题描述:
22/7×21/22×(22/7-22/3)×(-7/22)=?
答
22/7×21/22×(22/7-22/3)×(-7/22)
=-21/22×(22/7-22/3)
=-21/22×22/7+21/22×22/3
=-3+7
=4