199.7×19.98-199.8×19.96

问题描述:

199.7×19.98-199.8×19.96

199.7×19.98-199.8×19.96
=199.7×19.98-19.98×199.6
=19.98×(199.7-199.6)
=19.98×0.1
=1.998