数学题125×0.1999+2×1.25×19.99+1250×0.01999

问题描述:

数学题125×0.1999+2×1.25×19.99+1250×0.01999

原式=
125×0.1999+2×125×0.1999+125×0.1999
=0.1999×(1+2+1)×125
=0.1999×500
=99.95

125×0.1999+2×1.25×19.99+1250×0.01999
=125×0.1999+2×1.25×19.99+1250×0.01999
=1.25X19.99+2X1.25X19.99+1.25X19.99
=19.99X(1.25+2X1.25+1.25)
=19.99X5
=20X5-0.01X5
=100-0.05
=99.5