用简便方法计算:10.37×3.4+1.7×19.26=_______________________.1.25×32×0.25=________________.
问题描述:
用简便方法计算:10.37×3.4+1.7×19.26=_______________________.1.25×32×0.25=________________.
3.84×101-3.84=____________________.3.51×49+35.1×5.1+49×51=___________________________.1994×19951995-1995×19941994=_________________________.
答
10.37×3.4+1.7×19.26
=10.37×3.4+1.7×2x9.63
=10.37×3.4+9.63×3.4
=(10.37+9.63)×3.4
=20×3.4
=68
1.25×32×0.25
=(1.25×8)x(4×0.25)
=10x1
=10
3.84×101-3.84
=3.84×101-3.84x1
=3.84×(101-1)
=3.84×100
=384
3.51×49+35.1×5.1+49×51
=3.51x49+3.51x51+49x51
=3.51x100+49x51
=351+49x51
=351+(50-1)x(50+1)
=351+2500-1)
=350+1+2500-1
=2850
1994×19951995-1995×19941994
=1994×(19950000+1995)-1995×(19940000+1994)
=1994×1995×10000+1994×1995-1995×1994×10000-1995×1994
=0